Wild Staircases

Thinking for a minute that this is a roller coaster would surely make sense, but its not. This is a staircase that people actually able to walk on. Could you imagine walking on this thing. Talk about being out of breath for days after words.
"It looks like any old roller coaster, with curves and heart-stopping loops. But instead of zooming by, people are walking—on inclines fitted with steps. This creation in Germany's Rhine Valley is an interactive sculpture, but it’s also one of the world’s most unique staircases."