Ask anyone who works in a theme park and they will tell you the most common question that guests ask is "Where's the washroom? To try and make it less so it is important we make some highly visible signs. We'll do that while still having the signs fit into the theme of the park.
The signs will be routed from Precision Board high density urethane and then painted up to match the rest of the park.
Even with the highly visible signs on the doors of all the washrooms it is still my bet guests will constantly ask where they are. :)