Sorry - it's in Kentucky. (Mammoth / Flint Ridge system, well over 350 miles total of surveyed passages.)
The state with the largest cave system in the United States is Kentucky. The Mammoth Cave National Park in Kentucky is home to the world's longest known cave system, with over 400 miles of explored passageways.
The hutchison salt mine, also known as the Underground Salt Museum, is located 650 feet underground. It covers an area of approximately 30 acres and is one of the largest underground salt mines in the world.
The largest discovered underground labyrinth is the cave network found in Mammoth Cave National Park in Kentucky. While the Carlsbad Caverns can boast the largest single chamber in the US, the labyrinth at Mammoth is the longest ever found in the entire world.
Not a very good question. Longest in passage length: Flint Ridge / Mammoth Cave system (USA) Largest single chamber: Sarawak Chamber (Sarawak!)
The Hall of the Giants or the Big room is the largest cavern in New Mexico and one of the largest in the world. The cavern has 357,469 square feet of floor space and can be found in the Carlsbad Caverns at the Carlsbad Caverns National Park just a short way from Carlsbad, New Mexico.
Sarawak Chamber is largest underground chamber in the world by area. It is in Borneo.
in toronto ---- Montreal's underground city is the largest underground complex in the world.
The Sarawak Chamber is the largest known cave chamber in the world. The Sarawak Chamber is a cave that is located underground in the country of Malaysia.
Kentucky.
The Mammoth Cave
The London Underground is the largest in Europe and the oldest in the world.
The Sarawak Chamber in Gunung Mulu National Park, Malaysia, is considered the largest-known underground chamber in the world. It measures about 2300 feet (700 meters) long, 1300 feet (396 meters) wide, and 230 feet (70 meters) tall.
The London Underground, commonly known as the Tube, is the oldest metro system in the world. It opened in 1863 and has since grown to become one of the most extensive systems globally.
The New York subway system currently has 468 underground stations. It is the largest in the world and an average 5.4 rides take place every single day.
carlsbad caverns
Pakistan has the largest canal irrigation system in the world, known as the Indus Basin Irrigation System. It is fed by the Indus River and its tributaries, covering a vast area of agricultural land in Pakistan.
Pakistan has the world's largest canal based irrigation system