At the Adventure Mine near Greenland, in Ontonagon County, you clip into a rappelling harness and go down 80 feet to a lower level of a copper mine, in the dark, with a single light on your hard hat. The rope comes with the Miner’s Tour, and the Adventure Mining Company says it is the only tour where you rappel 80 feet to another part of the mine. It costs $78 for an adult, takes two to three hours, and the minimum age is 12. The mine it drops you into worked from 1850 to 1920.
There are four ways in, and only one of them hangs you off a rope for 80 feet. The Pure Michigan listing and a 2022 WFMK story both describe the shortest option as a 45 minute underground walk. The operator’s own site says the 45 minute limited mobility tour is a ride, in a side by side UTV that drives into a portion of the mine, by special request. Nobody walks that one.
The rope, the bridge and the slide
The Miner’s Tour starts like the Prospector’s Tour, through the No. 1 adit, where solid pieces of native copper weighing hundreds of pounds sit where earlier miners left them. Then it splits off. Everyone is provided a harness, rappelling equipment and safety training, and the company asks that you be healthy enough to walk uneven, steep terrain. After the rappel you crawl through several small areas and hike through some of the oldest parts of the mine.
Getting out is your call. One way is a swing bridge across a 30 foot chasm, with an overhead safety line you clip into as you cross. The other is what the company calls the traditional 10 foot slide. The company’s FAQ recommends rappellers be at least 13 and 70 pounds, a notch stricter than the tour page.
Who runs it now
The mine is a Keweenaw Heritage Site, an official partner of Keweenaw National Historical Park, but privately owned. The owner and operator is Matthew Portfleet, Director of Mine Safety and Health at Michigan Technological University. The company says it has offered tours since 2004.
A mine that never paid
The company’s history page says the Adventure was discovered in 1848 and formed as the Adventure Mining Company in 1850 with $200,000. The first year produced 12,000 pounds of copper and little profit, so individuals were let in to mine on their own and pay the company a percentage of the profits. Because the rock carried silver as well as copper, the company says the speculation has been that those miners walked off with much of the silver.
In 1898 the Adventure Consolidated Copper Company joined the Adventure with the Hilton-Ohio and Knowlton mines, and more than $2 million still left investors disappointed. WFMK’s account has production stalling in 1908, restarting during World War I, stopping in 1917 and closing for good in 1920. Across the whole run, miners took out more than 11 million pounds of native copper.
Michigan Tech’s Keweenaw Geoheritage site says the Adventure was opened on prehistoric excavations dating to about 5,000 years ago. Its deepest shaft, the No. 3, ran 13 levels and 1,300 feet down along the ore body. The company’s verdict is that there is probably more copper and silver still down there than has ever come out.
Sources: Adventure Mining Company; National Park Service, Keweenaw National Historical Park; Michigan Technological University, Keweenaw Geoheritage; Pure Michigan; WFMK; Wikipedia.
Go See It
Adventure Mining Company
- Hours
- Monday to Saturday 9 a.m. to 6 p.m., Sunday 11 a.m. to 6 p.m., Eastern time. Closed Wednesdays after Labor Day
- Cost
- Prospector's Tour, 1.5 hours: $38 adults, $16 ages 6 to 12, under 6 free. Miner's Tour (the rappel), 2 to 3 hours: $78, ages 12 and up. Captain's Tour, 5 to 6 hours: $175, ages 13 and up
- Season
- Memorial Day through mid-October. Tours run rain or shine
- Drive
- From Marquette: About 1 hour 48 minutes and 102 miles via US-41 and M-38 (Google Maps route, read Sept. 26, 2026)
From the Bridge: About 4 hours 28 minutes and 265 miles via M-28 W, with the Mackinac Bridge toll (Google Maps route, usual traffic, read Sept. 27, 2026) - GPS address
- The mine says to put 1100 Plank Rd., Greenland, MI 49929 into your GPS.
- Tour times
- Last Prospector's Tour starts 4:30 p.m. Last Miner's Tour starts 3 p.m. Captain's Tour Tuesdays and Saturdays at 10 a.m., reservation required.
- Booking
- Walk-ins welcome as availability allows. Call ahead for a group or a specific tour: (906) 883-3371, or book at https://adventureminetours.com/.
- Limited mobility
- A 45-minute tour by side-by-side UTV into part of the mine, by special request. You need to be able to transfer to a seat in the vehicle. Call ahead.
- What to wear
- On the Miner's Tour expect mud and water. Light jacket, good walking shoes, long pants. No open-toed shoes.
- Call first
- Prices and hours change; call before you drive.
More worth reading
Sources, credits, and reporting details
Sources & accountability
How this story was reported
Editorial methodAggregation
Last verifiedSep. 26, 2026
Corrections statusNo material correction note is recorded on this article.
AI assistanceResearched and drafted with AI tools. Reviewed and approved by editor Keegan O’Brien.
Verification note: Sources read and checked Sept. 26, 2026.
Primary sources
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Rappelling harness, down 80 feet to a lower level of the mine
"Use a rappelling harness and gear to descend 80 feet to a lower level of the mine"
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Underground Mine Tours – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Down a mine shaft in the dark
"If you want to try rappelling down a mine shaft in total darkness and crawling through low areas and down slopes, this is for you!"
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Underground Mine Tours – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: A single light on your hard hat
"Experience the mine as the miners would have over 160 years ago with a single light on your hard hat."
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: The only tour where you rappel 80 feet to another part of the mine
"This is the only tour where you rappel 80 feet to another part of the mine."
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Miner's Tour: $78 adult, two to three hours, minimum age 12 (also Go See It / Cost)
"Adult: $78" / "Duration 2-3 hours" / "Minimum Age 12 years old"
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Underground Mine Tours – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Copper mine near Greenland that worked from 1850 to 1920
"The Adventure Mine is a copper mine near Greenland, Michigan that operated from 1850 to 1920."
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Underground Mine Tours – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Four ways in (four tours: Prospector's, Miner's, Captain's, Limited Mobility)
"Prospector's Tour" "Duration: 1.5 hrs | Ages: All"; "Miners's Tour" "Duration: 3 hrs | Ages: 12 & up"; "Captain's Tour" "Duration: 5-6 hrs | Ages: 13 & up"; "Limited Mobility Tour" "Duration: 45mins | Ages: All"
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Adventure Mining Company | Michigan — Pure Michigan (Travel Michigan)
Accessed Sep. 26, 2026.
Supports: CORRECTION, wrong claim: Pure Michigan describes the shortest tour as a 45 minute underground walk
"Four distinct tours are offered: a45-minute underground walk, a one-hour-and-20-minute underground hike, athree-hour underground tour that includes rappelling down an 80' shaft, and a six hour long excursion to the second level of the mine" (run-together words as returned by the page)
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Underground Mine Tours – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
"Limited mobility tours are available by special request. Participants must be able to transfer to a seat in our vehicle (Side by Side UTV). These tours would last about 45 minutes and drive into a portion of the mine."
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Miner's Tour starts like the Prospector's Tour, through the No. 1 adit
"This tour begins the same as our Prospectors Tour, including entering the No. 1 adit to see solid pieces of native copper and exploring the largest rooms in the mine. Next, this tour parts ways to offer a truly unique experience."
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Prospector's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Solid pieces of native copper weighing hundreds of pounds left behind by earlier miners
"Enter by the No. 1 adit and see solid pieces of native copper weighing hundreds of pounds left behind by earlier miners."
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Harness, rappelling equipment and safety training provided; good health, uneven steep terrain
"All participants will be provided with a harness, rappelling equipment, and proper safety training." / "in good physical health and able to negotiate walking on uneven and steep terrain"
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Underground Mine Tours – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
"Use a rappelling harness and gear to descend 80 feet to a lower level of the mine, crawl through several small areas, and hike through some of the oldest and most interesting parts of the mine."
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Swing bridge across a 30 foot chasm with an overhead safety line; or the traditional 10 foot slide
"cross our daring swing bridge" / "leave by the traditional 10ft slide" / "Spanning a 30ft chasm, our swing bridge leads you over a steep stope connecting the second level to the third" / "an overhead safety line that you will clip in as you cross"
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Frequently Asked Questions – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: FAQ recommends rappellers be at least 13 and 70 pounds
"We recommend a minimum age of 13 years, and a minimum weight of 70 lbs."
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Adventure Mining Company (U.S. National Park Service) — National Park Service, Keweenaw National Historical Park
Published Apr. 2, 2025. Accessed Sep. 26, 2026.
Supports: Keweenaw Heritage Site, official partner of Keweenaw NHP, privately owned
"SIGNIFICANCE: Keweenaw NHP Heritage Site" / "The Keweenaw Heritage Sites are official partners of Keweenaw National Historical Park, but are privately owned."
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About – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
"Matthew Portfleet is the Director of Mine Safety and Health at Michigan Technological University in Houghton, Michigan, USA. He owns and operates the Adventure Mining Company"
-
About – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Tours offered since 2004
"Since 2004, the Adventure Mining company has offered a variety of historic underground mine tours and mining educational workshops."
-
About – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Discovered 1848; Adventure Mining Company formed 1850 with $200,000
"culminates with the discovery and establishment of the Adventure Mine in 1848. In 1850 Thomas Howe and C. G. Husset formed the Adventure Mining Company." / "The company was begun with a capital investment of $200,000."
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About – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
"While 12,000 lbs of copper was mined the first year, investors saw little profit and the mine began to operate on the tribute system which allowed individuals to mine on their own and to pay a percentage of the profits to the company."
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About – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Silver as well as copper; speculation that those miners took much of the silver
"Because the Adventure Mine contained silver as well as copper, speculation has been that much of the silver was concealed and taken by the tribute miners."
-
About – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
"In 1898 the Adventure Consolidated Copper Company was formed joining together the Adventure Mine, the Hilton-Ohio Mine, and the Knowlton Mine." / "Although over $2 million was invested in the mine and it was considered to be one of the most promising mines in the area, it was a disappointment to the investors."
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Underground Mine Tours – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: More than 11 million pounds of native copper over the whole run
"During that time, miners removed more than 11 million pounds of native copper from the ground."
-
Caledonia and Adventure Mines – Keweenaw Geoheritage — Michigan Technological University, Keweenaw Geoheritage
Accessed Sep. 26, 2026.
Supports: Opened on prehistoric excavations dating to about 5,000 years ago
"the Adventure was opened on existing prehistoric excavations located on Adventure Bluff. These prehistoric workings date to about 5,000 years before the present-day and were very extensive."
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Caledonia and Adventure Mines – Keweenaw Geoheritage — Michigan Technological University, Keweenaw Geoheritage
Accessed Sep. 26, 2026.
Supports: Deepest shaft, the No. 3, 13 levels, 1,300 feet down along the ore body
"The deepest of these shafts, the No. 3, contained 13 levels and extended down 1300' following the ore body."
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About – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Probably more copper and silver still in the mine than has come out
"Today, there is probably more copper and silver in the mine than has been mined out in all the preceding years."
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Contact – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Where: 200 Adventure Ave, Greenland, MI 49929; GPS 1100 Plank Rd.; phone
"200 Adventure Ave Greenland, MI 49929" / "For GPS Navigation, use: 1100 Plank Rd. Greenland, MI 49929" / "(906) 883-3371"
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Contact – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Hours: Mon to Sat 9 to 6, Sun 11 to 6 Eastern; closed Wednesdays after Labor Day
"During the season we are open Monday-Saturday from 9-6 and Sundays from 11-6 Eastern." / "After Labor Day, we are closed on Wednesdays."
-
Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Hours: last Miner's Tour starts 3 p.m.
"Last tour begins at 3:00 PM ET"
-
Prospector's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Hours: last Prospector's Tour 4:30 p.m.
"Last tour begins at 4:30 PM ET"
-
Prospector's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Cost: Prospector's $38 adults, $16 ages 6 to 12, free under 6; fee included
"Adult: $38" / "Child 6-12yr: $16" / "Child 0-5yr: Free" / "Price includes a $5 per guest gear cleaning and inspection fee."
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Cost: Miner's $78 includes a cleaning and inspection fee
"Price includes a $10 per guest cleaning and inspection fee."
-
Captain's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
"Adult: $175" / "Traditional Pasty Lunch Included" / "Minimum Age 13 years old" / "Offered Tuesdays & Saturdays at 10:00 a.m." / "Reservations required" / "Price includes a $25 fee for Lunch and Gear inspection and Cleaning."
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Contact – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Season: Memorial Day through mid-October
"Our season begins Memorial Day and runs through mid-October."
-
Contact – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Booking: online or by phone
"please call ahead for availability" / "Book Online Now!"
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Frequently Asked Questions – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / Booking: walk-ins allowed, reservations highly recommended
"We do HIGHLY recommend reservations. Walk-in tours are allowed, but availability can be limited."
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Miner's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / What to wear: light jacket, good walking shoes, long pants, no open-toed shoes
"A light jacket, good walking shoes, and long pants are recommended. No open-toed shoes."
-
Prospector's Tour – Adventure Mining Company — Adventure Mining Company
Accessed Sep. 26, 2026.
Supports: Go See It / What to wear: helmets and headlamps provided
"Helmets and headlamps are provided."
-
Google Maps driving directions from Marquette — Google Maps
Accessed Sep. 26, 2026.
Read live in Chrome Sep 26, 2026 (Saturday): "Driving 1 hr 48 min, 101 miles via US-41 N and M-38 W, fastest route".
Additional reporting
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Adventure Mine — Wikipedia
Accessed Sep. 26, 2026.
Supports: Greenland is in Ontonagon County
"a copper mine in Greenland Township, near Greenland, Michigan in Ontonagon County, Michigan"
-
Inside An Old U.P. Copper Mine in Ontonagon County — WFMK 99.1 (Townsquare Media), John Robinson
Published Jun. 29, 2022. Accessed Sep. 26, 2026.
"A 45-minute underground walk"
-
Adventure Mine — Wikipedia
Accessed Sep. 26, 2026.
Supports: Conflicting date for tours (not used in text): Wikipedia says since 2005
"offered tours since 2005"
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Inside An Old U.P. Copper Mine in Ontonagon County — WFMK 99.1 (Townsquare Media), John Robinson
Published Jun. 29, 2022. Accessed Sep. 26, 2026.
Supports: Production stalled 1908, restarted in World War I, stopped 1917, closed for good 1920
"Production slowed to a halt in 1908, started up again during World War I, stopped again in 1917, and closed for good in 1920"
-
Adventure Mine — Wikipedia
Accessed Sep. 26, 2026.
Supports: Corroborates 1917 halt and 1920 closure
"Production finally halted in 1917 and the mine closed in 1920."
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michiganrailroads.com – Adventure Mine, Greenland, MI — michiganrailroads.com
Accessed Sep. 26, 2026.
Supports: Corroborates about 11 million pounds (not used as its own figure)
"approx. 11 million lbs. of refined copper"
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Adventure Mining Company (U.S. National Park Service) — National Park Service, Keweenaw National Historical Park
Published Apr. 2, 2025. Accessed Sep. 26, 2026.
Supports: Go See It / Cost: corroborates Prospector's-level prices
"Fees: Tours $38 Adults, $16 Children (6 to 12 years old), under 6 free."
Photo and media credits
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E5FFDFD6-A090-F781-EC127FCE1A0F75FA.jpg (featured, media 3025) — National Park Service / NPS Photo – Nathan Miller
Featured image record. Accessed Sep. 26, 2026. Public domain (NPS photo).
Supports: Image credit and licence.
Licence read off the source page Sep 26, 2026; 6000×3375 original, uploaded as a downscale.
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Kids_Take_a_Ride_in_the_Pinzgauer_Before_Entering_the_Adventure_Mine_-eef2e8f9-1.jpg (media 3026) — Wikimedia Commons / NPS Photo
Accessed Sep. 26, 2026. Public domain.
Supports: Image credit and licence.
Licence read off the source page Sep 26, 2026; 4288×3216 original, uploaded as a downscale.
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Copper_and_silver_-Mesoproterozoic-_1.05-1.06_Ga-_Adventure_Mine-_Ontonagon_Coun.jpg (media 3027) — Wikimedia Commons / James St. John
Published Sep. 15, 2010. Accessed Sep. 26, 2026. CC BY 2.0.
Supports: Image credit and licence.
Licence read off the source page Sep 26, 2026; 2662×1905 original, uploaded as a downscale.
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