### L2304 coral architecture on the Swahili coast > The new architecture was in mud and coral, then, by the thirteenth century, wholly in coral—stone houses, palaces, and other structures forming compact towns, often with courtyards. The switch to coral masonry may reflect the changing focus of the trade away from the Persian Gulf to the Red Sea, where coral buildings were in common use. Mangrove poles formed the ceilings, their length restricting the size of rooms, making small rooms a common feature of coastal architecture. I really need to do a deep dive on coral architecture for worldbuilding Magazine blog post - [[Beyond the Blue Horizon by Brian Fagan#L2304 coral architecture on the Swahili coast|View in Vault]]