Sweden has many mines that dot the landscape, many of which have been closed or abandoned. Some have been made accessible to the public, but often imposing strict rules and paths. This is not the case for the Tuna-Hästberg Adventure Mine, where almost nothing is off-limits. The mine dates back to the 1600s, but most of its 12.5 miles (20 kilometers) of tunnels were dug in the late 19th and early 20th-centuries. The tunnels go down about 1,700 feet (520 meters) underground but are filled with water up to the…
