So I am still, all these years later, intrigued by ancient cities and cultures. Here is one i never heard of. On the island of Temwen in Micronesia is a city built on a coral reef. They carved basalt and constructed the buildings in what appears to be a 'cabin' design one might find in the old west of the USA. By that i mean interlocking pieces of basalt.
What's more fascinating is that it was built on a coral reef. I hope they had good shoes. it was a canal city so well constructed the canals still work today. Take a gander, link below, be inspired!!!