Anadolu Hisarı is the older, smaller, more forgotten fortress — the one Bayezid I built in 1394, almost sixty years before Mehmed II built the one across the water. The two of them face each other now across the Bosphorus's narrowest stretch, seven hundred metres apart, like a slow conversation between Ottomans a half-century behind and a half-century to come.
Three kilometres on the Asian shore, mostly flat, the fortress at the start and the tea at the end. The 15F bus drops you at the village above the walls. Walk the fortress first — it's smaller than Rumelihisarı, more weathered, and the smaller scale lets you read it as a fortification rather than as a monument. The Göksu stream emerges into the Bosphorus a few hundred metres north; the Küçüksu Kasrı sits where it does because Abdülmecid liked the water meadow it overlooks.
Back through the village's wooden houses to a çay garden facing west. Rumelihisarı sits across the strait at the same scale Mehmed's masons saw in 1452. Bus back from the same stop, or push north for the Beykoz ferry if you want a longer return.
