Biathalon

<p>large stadium with several swimming pools at the bottom, and thousands of stair cases between the pools and along the walls

Athletes must run and swim from one high end of the building to the other high end

Run down several flights of stairs, and across several catwalks, down pillared halls, more stairs, into a pool, across the pool, up some stairs, across a platform, up more stairs, down again, another pool, up, down, pool, up, halls, up, up, up, up and up.

the sides are spectator seating</p>