The Stone Fortress (Shitoucheng) sits on a low bluff at the northern edge of town, the feature that gives Tashkorgan its name — Tashkorgan means "stone fortress" in Turkic languages. The visible walls are a mix of mortared rubble and mud-brick, much of it Qing-dynasty work over older foundations, and the curtain wraps an irregular plateau perhaps 150 metres across. A wooden boardwalk now climbs through the ruins and runs along the ramparts, which is the easy way up.
What the fortress really offers is the view. From the ramparts you look out across the Tagharma grasslands, the Tashkorgan River winding through them, and the Pamir peaks to the west and south. In summer the wetlands fill with grazing yaks and herders' tents, and the contrast between the dry stone walls and the green of the valley is the image most visitors take away. Early morning before the wind picks up is the best light; an hour is enough to walk the perimeter and read the small interpretive signs in Chinese and English.