Hidden Beneath Missouri: The Fascinating World of Bonne Terre Mine

Bonne Terre Mine is one of the most unique places we’ve ever toured—where else can you take a boat ride on the world’s largest subterranean lake inside a five-level underground mine? Located in the Missouri Ozarks, this historic site was once a major hub for lead mining, operated by the St. Joe Lead Company from 1862 until 1963. When the mine shut down, the pumps keeping it dry were turned off, and over time, the lower levels flooded, creating the massive crystal-clear lake that visitors can now explore by boat. During our visit, we took the walking and boat tour, getting a firsthand look at the vast caverns, towering rock formations, and remnants of its mining past.

Special Note: As of February 2025, Bonne Terre Mine is currently closed due to legal issues. We’ll cover more about that later in the post, but be sure to check for updates before planning a visit.

History of Bonne Terre Mine

Lead mining runs deep in Missouri- literally. The Bonne Terre Mine was at the heart of what was once the largest lead-producing region in the world, the Old Lead Belt. The first miners here were French explorers pulling galena ore from the surface back when this land was still part of the Louisiana Territory. By 1864, the St. Joseph Lead Company (or St. Joe) entered the scene, purchasing 946 acres around Bonne Terre and slowly buying out the competition. Mining shifted underground after 1870, following rich veins of lead deep into the earth and creating a vast network of tunnels and shafts.

This region was so heavily mined that over time, various mines from different companies started to connect underground. Eventually, the only thing separating them were artificial boundaries. It’s estimated that there are at least 300 continuous miles of subterranean tunnels beneath St. Francois County, making it one of the most extensive mining networks in the world. In 1869, an experiment at Bonne Terre led to the first-ever use of a diamond drill to locate lead ore. It was a game-changer, allowing miners to drill deeper and more accurately, and the method was eventually used nationwide. That same year, the first lead mining shaft in the U.S. was drilled 120 feet down, marking the official shift from surface to underground mining.

At its peak in the early 1900s, the mine was a massive operation, with three or more levels being worked at the same time. The upper mining level, about 55 feet below the surface, was the oldest, while the lowest point of the mine reached 400 feet down. Mining here used a “room and pillar” method, leaving behind thick rock pillars to support the ceiling. A narrow-gauge railroad system helped move ore and equipment around, with over 30 miles of track in use by the time the mine shut down. Mules were used underground to haul loads, and they even had their own stables in the mine, along with a barbershop and offices!

One of the more bizarre moments in the mine’s history happened in the 1920s when a blasting operation accidentally blew out part of someone’s backyard, unintentionally creating the mule entrance still used today. The mine operated until 1962, when production at Bonne Terre ended due to depleted ore and increasing costs. The following year, St. Joe moved operations to Viburnum, marking the end of an era for the Old Lead Belt. In 1973, guided tours began, giving visitors a chance to see the mine’s underground world firsthand. Today, Bonne Terre Mine is listed on the National Register of Historic Places, preserving its incredible history for future generations.

Tours of Bonne Terre Mine

Boat and Walking Tour

The most popular way to explore Bonne Terre Mine is the Boat & Walking Tour, which takes you 200 feet underground to experience this incredible subterranean world. The tour starts with a walk of about a third of a mile through tunnels filled with old mining equipment, learning about the history of lead mining in Missouri along the way. Once you reach the dock of Billion Gallon Lake (the world’s largest underground lake) you’ll board a pontoon boat for a peaceful 10-minute ride through the flooded mine. Along the way, you’ll see remnants of the past, including the No. 1 elevator shaft, submerged ore carts, towering wrapped pillars, and abandoned overhead catwalks. The tour lasts around 45–55 minutes and includes 65 steps in and out of the mine. Walk-ins are accepted, but reservations are recommended, especially in the summer or for groups larger than four.

Diving Tours

For those looking for a truly unique adventure, Bonne Terre Mine also offers guided scuba diving tours, allowing divers to explore the vast flooded sections of the mine. This is one of the most unusual diving experiences in the world, with multiple dive trails to progress through as you build your skills. The water stays around 60 degrees year-round, so a dry suit is recommended to stay comfortable. Divers start with basic exploration and gradually move on to more advanced sections, uncovering hidden tunnels, old mining equipment, and eerie underwater structures left behind when the mine was abandoned. Each dive is guided, ensuring safety while making the most of this unforgettable underground experience.

BlueWorldTV has a great YouTube video of diving the mine if you want to see more.

Our Bonne Terre Mine Tour Experience

We mentioned in our Missouri Mines post that our two weeks in the Missouri Ozarks accidentally turned into a geology-themed trip, and Bonne Terre Mine was one of three mining-related sites we visited. We did the walking and boat tour, which cost $68.88 for both of us- definitely on the pricey side compared to similar tours we’ve done, but still worth it for such a unique experience. Our tour group was fairly small, and our guide was knowledgeable, sharing details about the mine’s history, the St. Joseph Lead Company, and how mining operations worked underground. Seeing the massive, hand-dug rooms in person was absolutely mind-blowing. Photos and videos just don’t do the scale justice. The boat ride, while cool, was much shorter than we expected, just making a quick loop instead of exploring more of the flooded tunnels. Above ground, the site had a small souvenir shop where we got our tickets, a separate building with restrooms, and an area for divers with lockers and a lounge. There were also some pieces of old mining equipment scattered outside. We took our tour on February 8th, and when we went to write this post, we were surprised to find that as of February 11th, the mine was temporarily closed due to pending legal matters.

The Legal Situation at Bonne Terre Mine

Disclaimer: I’m not a lawyer. I have a criminal justice degree that included learning how to read and analyze court cases- but this is still the best attempts by an amateur to put together information from multiple court cases. Everything here is based on my reading of publicly available documents from the Missouri court system.

The legal dispute over Bonne Terre Mine is between Doe Run (the current name of what was once St. Joseph Lead Company) and West End Diving (the company that has operated tours at the site for decades). Doe Run still owns the mine and mineral rights but has leased it to West End Diving, which began renting in the 1980s.

There have been a few different court cases between the two companies starting back in 2019. The main case relates to Doe Run suing West End for not paying rent since 2006. West End argued against this case because from 1999 to 2006, both parties exchanged letters about a potential sale of the mine, so they should own it and not owe rent. In September 2024, the case went to trial, and in October 2024, the court ruled in favor of Doe Run for unlawful detainer and breach of contract. The court ruled that no legally enforceable contract was ever finalized. Even if a contract had existed, the 10-year statute of limitations had passed on closing the sale. They also ruled against West End’s counterclaim of a quiet title based on adverse possession (more on that later). The court ruled that Doe Run would get restitution of the premises (possession of the mine) and that the Sheriff’s office would put them in possession of the premises. 

Going back to that quiet title counterclaim, in September 2024, Sadew II LLC (one of many companies owned by the same people as West End Diving) filed a petition to quiet title and for equitable relief, arguing that Doe Run only owns mineral rights, not the entire property. Sadew claimed that because Doe Run recently stated that mining was no longer viable, they had lost their right to mine, and therefore their mineral estate should be terminated, giving Sadew full ownership of the property. They also argued that Doe Run’s use of law enforcement to enforce the October judgment interfered with their right to use and enjoy their property. This case was unsuccessful.

West End Diving filed with the appellate court in January 2025. Meanwhile, on January 29th the writ of execution was issued to the Sheriff’s department to restore possession to Doe Run. The writ is signed as having been completed in February 11- which is the date of the first Facebook post from the mine saying it was closed to tours.

Then in February, West End Diving’s affiliated companies—Sadew II LLC, Sadew III LLC, Sadew V LLC, and Sadew IX LLC—filed for a temporary restraining order (TRO). These companies, owned by the same people as West End Diving, argued that they hold surface rights to the property and that the mine’s sewer, electrical, internet, and plumbing systems connect to the surface estate. They also claimed ownership of personal property inside the mine, like air tanks and dock structures, and argued they would suffer irreparable harm if unable to access and maintain these systems. The court granted a TRO to maintain the status quo, preventing Doe Run from interfering with access to infrastructure directly affecting the surface property. However, the TRO did not stop the sheriff from restoring Doe Run’s possession of the mine.

I’m writing this post on February 27, so this is all pretty fresh. I’ll keep an eye on the case and update this post if they ever do reopen again, but for us this was definitely a reminder to get out and explore while you can! We’ve had other places that we wanted to visit close not long after we went, and others that closed right before we went- so go see as much as you can while you can!

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