What are these large circular buildings? (Image attached) : r/whatisthisthing

What is this attachment and why is it round? : r/whatisthisthing

Hopefully this post works! Three-foot wide circular metal ring/pipe, about 4 thick, stony concrete around it - not level with the ground. Discovered after a hundred year flood in my garden. The

Three circular (10+ft in diameter) objects with hot and cold water outputs in each of the “seats”? : r/whatisthisthing

5 Unusual Circular Buildings

Three circular (10+ft in diameter) objects with hot and cold water outputs in each of the “seats”? : r/whatisthisthing

Round buildings hi-res stock photography and images - Alamy

Architectural Drawings: 8 Circular Plans That Defy Convention - Architizer Journal

Image result for circular building Circular buildings, Round house, Residential architecture

What is this 20'-30' concrete tower in the woods? : r/whatisthisthing

Circle shaped building hi-res stock photography and images - Alamy

Corroded, half-buried, iron, circular object found in the woods approximately 12-14 inches across : r/whatisthisthing

WITT? Circular metal (?) plate in old apartment. Building probably built sometime in the mid 1800s. It's been painted over so I can't tell what material it is but there is a