There is about 120 different ones.
38,974 indoor movie theaters
Han Chiang Indoor Stadium , 1966(renovated in 2007)
This question has know actual answer because people have different opinions, but I believe it is basketball.
USSF is the United Stated Soccer Federation. This is the national association affiliated with FIFA and which fields the US national team. There is also MLS, which stands for Major League Soccer, and is the foremost league for professional soccer in the United States.
23
4
many
About 37,813 US NFL football fields.
About 105 (105.876124933827422) US NFL football fields.
1
Around 70 million play in US.
About four (3.78129) US NFL football fields.