Siphon

View of a portion of a “siphon” of an aqueduct system that brought water to the Roman Baths of Ankara.

Note how each stone was hollowed out and the “collar and sleeve” arrangements that sealed the system.

---

The Roman Baths in Ankara are located on a low large mound in the Ulus district.  These baths have been excavated and date to the reign of the Roman Emperor Caracalla (A.D. 211-17).  They were in use until the sixth century A.D.