North of Partheni you will find a vaulted church built in the 18th century. The walls are decorated with unique frescoes of non-Byzantine style. During the years of the dictatorship, the church was ruined until a group of political prisoners (Manolis Glezos and painters Kyr. Tsakiris, Ant. Karagiannis and T. Tzaneteas) decided to repair it. The three exiled painters depicted the history of the island on the interior walls, using prisoners, women of Leros and gendarmes as their models. Since the beginning of the project in 1969 and until its completion eight months later, the islanders remained very supportive. However during the political changeover, people from conservative or religious groups, painted the wall white. Poet Yannis Ritsos was also one of the exiles on the island. The place inspired him to write "18 Little Songs of the Bitter Homeland" which was later set to music by Mikis Theodorakis.

Today the church of St. Kioura is a historic monument and it is protected by the state.