Cool bike park underground

[vav]

Would kill for something like this here in NE

http://www.louisvillemegacavern.com/attractions/6/mega-underground-bike-park

http://www.grindtv.com/outdoor/excursions/post/gigantic-bike-park-open-abandoned-mine/

[pinkshogun]

https://www.youtube.com/watch?v=GF_WQ0eC9Bg

[ceolwulf]

I want an underground velodrome. Just an oval tunnel. I keep imagining how cool that would be.