An oval wind tunnel track with lanes for skating, running, cycling, etc.

There would be a barrier in the centre to separate the airflows and waist-high barriers to separate the different activities/surfaces in the concentric lanes.

But why? You ask. Oh ye of little imagination. For the practically inclined, it's an opportunity to practice tilting into a headwind. Later, the more frivolous don wing suits and head downwind, skating, running and jumping at frankly reckless velocities.
-- marklar, Apr 23 2024

How and where do you place the fan(s)? https://www.grc.nas...rplane/tuncret.html
[a1, Apr 23 2024]

Jet fans https://global.kawa...iable%20Jet%20Fans.
[a1, Apr 27 2024]

This is brilliant! [+]

And welcome back! Long time no see!
-- doctorremulac3, Apr 23 2024


//How and where do you place the fan(s)?// There could be stadium style seating, and a bar area with more informal tables, but this viewing area probably needs to be separated from the tracks by large plate glass windows.
-- pocmloc, Apr 24 2024


Good point, [pocmloc]! And then there's the question about how to keep the wind moving around the track. Need some kind of machinery, could call them air moving thingies, I guess...

Windbags?

Bloviators?
-- a1, Apr 24 2024


The fans could simply be like those used in road tunnels. It would be more interesting to use air entrainment through large arches, like Dyson fans.

Hmm, how large would your shoes need to be for an air hockey rink?
-- marklar, Apr 27 2024


// like those used in road tunnels //

Cool - HB gives me reason to go look up things I never thought about before. TIL Kawasaki Heavy Industry makes a lot of tunnel ventilators (link), and I think their jet fans would look awesome above your track.
-- a1, Apr 27 2024



random, halfbakery