PLOESCI (Ploescii), the capital of the department of Prahova, Rumania; at the southern entrance of a valley among the Carpathian foothills, through which flows the river Prahova; and at the junction of railways to Buzeu, Bucharest and Hermannstadt in Transylvania. Pop. (1900), 42,687. As the name Ploesci (pluviena, rainy) implies, the climate is moist. The surrounding hills are rich in petroleum, salt and lignite. There are cardboard factories, roperies, tanneries and oil mills. Ploesci possesses schools of commerce and of arts and crafts, several banks, and many synagogues and churches, including the Orthodox church of St Mary built in 1740 by Matthew Bassarab.