Pergamon
Pergamon lies on the north edge of the Caicus plain in the historic region of Mysia in the northwest of Turkey. The Caicus river breaks through the surrounding mountains and hills at this point and flows in a wide arc to the southwest. At the foot of the mountain range to the north, between the rivers Selinus and Cetius, there is the massif of Pergamon which rises 335 metres above sea level. The site is only 26 km from the sea, but the Caicus plain is not open to the sea, since the way is blocked by the Karadağ massif. As a result, the area has a strongly inland character. In Hellenistic times, the town of Elaia at the mouth of the Caicus served as the port of Pergamon. The climate is Mediterranean with a dry period from May to August, as is common along the west coast of Asia Minor.
Pergamon
After the Sack of Constantinople in 1204 during the Fourth Crusade, Pergamon became part of the Empire of Nicaea. When Emperor Theodore II Laskaris () visited Pergamon in 1250, he was shown the house of Galen, but he saw that the theatre had been destroyed and, except for the walls which he paid some attention to, only the vaults over the Selinus seemed noteworthy to him. The monuments of the Attalids and the Romans were only plundered ruins by this time.