Naos Episkopis, Eastern Orthodox mausoleum in Sikinos, Greece

Naos Episkopis is a small ancient building of grey marble, whitened with lime, measuring 10.4 by 7.16 metres. Its west front has two columns 4.9 metres tall with Doric capitals, and the south wall is held by stone buttresses. Inside, a pronaos and cella are covered by a dome added when the tomb became a church.

The building dates to the third century when it was built as a tomb for a wealthy person. Over time it was adapted for religious purposes and became a place of worship in the Byzantine period.

The church is dedicated to the Theotokos and known as Episkopi. A 17th-century patriarchal sigillion records its renovation by Nikolaos Serfiotis, uncle of the Archbishop of Sifnos Athanasios, who was granted its care. Simple structures around the church sheltered pilgrims during festivals.

The monument opened to the public on 3 September 2022, so it can now be visited. It stands on the southern part of Sikinos's central ridge, about a 1.5-hour walk from Chora, surrounded by terraced fields; the crypts below the cella are reached by a path on the south side.

During the 2017 restoration, a sealed cist grave was found in a crypt beneath the church, holding the remains of a woman of the 2nd or 3rd century AD. With her lay rings, gold bracelets, a necklace, a brooch, and glass and metal vessels. The grave inscription names her Neiko, likely the woman for whom the mausoleum was built.