The Water Temple - Phased DnD battlemap

Across the nations of the world, it denoted that many, even most civilizations build along the sea, for trade and food. As a cartographer, I can say without doubt over the ages the seas have crept closer and closer. Leads one to wonder, What history of the ancient world sleeps under the tide, What volumes could we fill if only we had gills.
-Idia Holly

Note: Ancient temple structures are unreliable. Especially puzzles, And double so for moving parts.