Istanbul
Does the Barrier block a Family Member, the Fountain, or bonus cards?
A Family Member sent from the Police Station is not limited by paths, so it probably crosses the Barrier, though the rules say nothing explicit. The Fountain still works with a Barrier next to it. A bonus card can repeat an action across a Barrier, and a Mosque tile can still be used. At the Catacombs, a Barrier gives you the good and nothing else.