Sesimbra () is a municipality of Portugal, in the Setúbal District, lying at the foothills of the Serra da Arrábida, a mountain range between Setúbal and Sesimbra. Due to its particular position at the Setúbal Bay, near the mouth of the Sado River and its natural harbour, it is an important fishing town. The population in 2011 was 49,500, in an area of 195.47 km². The present Mayor is Francisco Jesus. General information Besides professional fishing and sport fishing (mainly of swordfish), the most significant revenues in Sesimbra come from tourism. The town is known for its beaches, fish restaurants and nightlife. The original name of Celtic origin was Cempsibriga, meaning the high place (briga) of the Celtic tribe the Cempsi. Close by, on a mountaintop, above sea level, lies strategically (the ruins of) the Moorish castle. It was taken from the Moors, during the Portuguese Reconquista in the year 1165 by king Afonso Henriques with the help of Frank Crusaders. The battlements afford a panorama over Sesimbra, its harbour and the surrounding countryside. In addition to the castle, Sessimbra has two forts dating back to the 17th century; the Fortress of Saint James of Sesimbra in the centre of town and the Fort of São Teodósio da Ponta do Cavalo. The former contains a museum covering Sesimbra's history as a fishing village. During the Age of Discoveries, Sesimbra became an important seaport. Even king Manuel I lived here for a while. In the 17th century the fort Fortaleza de Santiago was built along the beach, as part of Portugal's coastal defence. On 3 June 1602 an English fleet defeated a Spanish galley fleet and in addition captured a large Portuguese carrack and severely damaged the fort. It was even used in the 18th century by Portuguese kings as a seaside retreat. A tourist travelling to Sesimbra can appreciate its beaches, traditional fish restaurants and the Arrábida National Park. Sesimbra is a popular diving location close to Lisbon and the most famous dive site is the wreck of the River Gurara, a Nigerian cargo ship, that sunk in 1989 with the loss of 45 sailors. Close to the Moorish castle is the church Nossa Senhora do Castelo. It stands on the spot where king Sancho I built a Romanesque chapel in the early 13th century, leading to the creation in 1388 of the parish of Nossa Senhora do Castelo de