The Historical Archives Museum of Hydra, Saronic: This museum was founded in 1918 and it is housed in an elegant stone mansion that belonged to the local shipowner Gikas Koulouras. In 1996, the building was renovated and today it is the most impressive mansion at the port of Hydra. Right next to the entrance, there are some old anchors, signs of the rich nautical impression of the island.
The museum hosts the historical archives that were kept for years inside the Church of Assumption of Virgin Mary. These archives include educational, administrative and religious archives, manuscripts from the Greek Revolution, old books, map, and others. The museum also hosts relics from the Balkans Wars and the two world wars, traditional costumes, carvings, naval instruments and painting works.