Although St. George's Castle was constructed by the Moors, it's on the site that was the beginning of the city and had previously been fortified by Romans and Visigoths. At the main entrance is a statue of Dom Afonso Henriques, who in 1147 besieged the castle and ultimately drove the Moors from Lisbon. Within the walls are ramparts, towers, and remnants of a palace that was a residence of the kings of Portugal until the 16th century. From the Câmara Escura in the Torre de São Lourenço you can spy on visitors going about their business below. Named after Roman Lisbon, "Olisipónia" is a multimedia exhibit on the city's history of the city: images projected onto a large wall convey the drama of such episodes as the Great Earthquake of 1755. The rest of the well-kept castle grounds are home to swans, turkeys, ducks, ravens, and other birds, and the outer walls encompass the medieval church of Santa Cruz, a few simple houses, and some restaurants and souvenir shops. Panoramic views of Lisbon can be seen from the walls, giving a very clear perspective of the layout of the city, the broad harbor, and the towering Ponte 25 de Abril suspension bridge; be careful of the uneven footing.
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