The Serapeum was a vast temple and associated complex built at the foot of the acropolis of Pergamum during the reign of the Roman Emperor Hadrian. The temple was dedicated to the worship of the Greaco-Egyptian god Serapis and to the Egyptian goddess Isis. The temple complex was huge and had to cross the nearby Selinus river supported by two very large vaulted tunnels which channel the waters to this day. The majority of the courtyard lies under the modern town buildings to the west of the temple. Originally covered with marble facings only the red brick superstructure of the temple remains. During the late Roman/early Byzantine period a church dedicated to St John was built inside the main temple. The church is in poor preservation when compared to the surrounding temple. However due to the instability of the remaining structure of the temple it is not possible to enter it and view the church remains. The temple is flanked by two contempraneous rotunda, one of which is a functioning mosque while the other is open to the general public.
Late Antique portion of the city walls on the south west edge of the Lower Agora on the acropolis. Much like many other Late Antique defences these fortifications are made up of significant amounts of spolia that was robbed from nearby dilapidated or ruined buildings. These walls were likely built as the city contracted in Late Antiquity.
The most northerly fortified section of the acropolis of Pergamum immediately north of the Temple of Trajan. Within this part of the fortifications lie several warehouses or arsenals believed to be for the storage of provisions, weapons and ammunition. Excavations have recovered significant numbers and varying sizes of stone shot for catapults.