Ye Olde Inn

This is probably a stupid question, but I just want to make sure I'm doing this right.
If there is a hidden trap in the middle of a room, such as a pit trap--
Do the heroes have to END their turn on it to spring it? Or do I have to "watch" the path they take and stop them if the walk across that space.
Just to verify, I'm "NOT" talking about "jumping a trap", I just wanna know if i should make the show me each space they step on.

Yes, i think most people play that if a Hero steps on a pit trap, having not searched the area, they have to be stopped - ending thier go and losing a body point.
You do have to see which route and the exact sqaures characters step on on thier movement.

I don't know of anyone that plays that you only activate a trap if you end your turn on that square.

OK, thanks. Yea, that would be pretty lame if they have to end their turn on it to trigger it. Would have been easier for Zargon/Morcar to keep track of unsprung traps that way tho.