Explore The northern mainland Thessaloníki and around Mount Olympus and around Véria and Vergina Northwest Macedonia Halkidhikí Northeastern Macedonia Kavála and around Thrace Share Above Odhós Kassándhrou, the street parallel to Ayíou Dhimitríou, rises the Upper Town or Áno Póli, the main surviving quarter of Ottoman Thessaloníki. Although the streets here have long been swamped by new apartment buildings, they remain ramshackle and atmospheric, a labyrinth of timber-framed houses and winding steps. In the past few years many of the older houses have been bought up and restored and it is justifiably one of the city’s favourite after-dark destinations. Sections of the fourteenth-century Byzantine ramparts, constructed with brick and rubble on top of old Roman foundations, crop up all around the northern part of town. The best-preserved portion begins at a large circular keep, the Trigónion or Chain Tower (so called for its encircling ornamental moulding), in the northeast angle where the easterly city walls veer west. A much smaller circuit of walls rambles around the district of Eptapýrgio (Seven Towers), enclosing the old eponymous acropolis at the top end. For centuries it served as the city’s prison until abandoned as too inhumane in 1989; it is described as a sort of Greek Devil’s Island in a number of plaintive old songs entitled Yedi Küle, the Turkish name for Eptapýrgio.