There is an annoying bug with fog of war and ruins.
When you unfog a ruin for the first time it shows as 'unexplored' even if it has actually been explored. You must hit refresh on the browser to get the actual state of the ruin.
This bug has caused me on more than one occasion to move my hero to a ruin only to find it has no gold which wastes a full turn of movement.
On your next turn it reports the correct state.
Ideally in Beta4/5 you would have another graphic image to show explored ruins in a different manner so you didn't have to click on them. DLR for example showed a tower as broken to indicate it was already searched. Caves (which you don't have) had eyes peering out of them when a monster was there and no eyes when it was explored etc.
KGB