St. George's Castle:
It might have been where the Portuguese capital began. Its occupation is believed to have predated the Romans -- the hilltop was used as a fortress to guard the Tagus and its settlement below. Beginning in the 5th century A.D., the site was a visigothic fortification; it fell to the Saracens in the early 8th century. Many of the existing walls were erected during the centuries of Moorish domination. The Moors held power until 1147, the year Afonso Henríques chased them out and extended his kingdom south. Even before Lisbon became the capital of the newly emerging nation, the site was used as a royal palace.
For the finest view of the Tagus and the Alfama, walk the esplanades and climb the ramparts of the old castle. The castle's name commemorates an Anglo-Portuguese pact dating from as early as 1371. (George is the patron saint of England) Portugal and England have been traditional allies, although their relationship was strained in 1961 when India, a member of the Commonwealth of Nations, seized the Portuguese overseas territories of Goa, Diu, and Damão.