The kale (castle) or hisar (fortress) overlooks Afyon from a craggy rock and the steep path up is signposted opposite Ulu and Yukarı Pazar Camis. The strenuous approach passes Ottoman guard towers on what was quite the formidable defensive structure. A taxi up costs about ₺15.
Hittite King Mursilis II built the first castle here, circa 1350 BC. Since then, various rulers have restored the original kara hisar (black fortress) – most recently the Turkish government, with unorthodox white masonry. In 2004 the state also renamed Afyon, named after the afyon (opium) that was cultivated here, as Afyonkarahisar ('Black Castle of Opium'), thus shifting the limelight to the castle from the less savoury history of opium production.
Although the castle is empty, the views from the 226m-high summit are spectacular. However, by night it is unlit, so do not leave it too late if walking down.
