Hi,

https://www.openstreetmap.org/way/1285973569

These locations are turning circles, not parking areas. :) Yes, they are much abused.

The way can be tagged like the rest of the highway=*

The 'junction' is tagged like this: https://www.openstreetmap.org/node/11687931360

If there are dead ends, they can be tagged like this: https://www.openstreetmap.org/node/11687931359

