It is one of the many monumental fountains in Ephesus. It was dedicated to the city by the rich Roman Pollios Sextiliues. This fountain was build and dedicated to Roman Emperor Domitian. It is just opposite the temple of Domitian.
Nowadays a restoration will start in this foundation. The arch was restored a few years ago; the mythological group of Odysseus and the Polyphemus were depicted. Some relics are in the Museum of Ephesus/Selcuk. The fountain was built in the 1st Century AD.