As far as I know someone set a caravan on my tent location, but it has been stolen before I could check how it does (not) work.
Maybe if you stop at point where are two locations the list (with short names) of all should appear near the triangle? When you override with a mouse it shows detailed description.
BTW. you can get encounters on caravans/cars (which are seen globally) and bases/caves/tents. Looks weird a bit.