Yogmaya Temple, Delhi

The building is not old; the worship is. Whatever stood here, and its first architecture is put at 300-200 BCE, was rebuilt again and again by the people living around it after the Mamluks destroyed it: Hemu raised it from ruins, a rectangular Islamic-style hall went up under Aurangzeb, and the temple you walk into dates from an early nineteenth-century restoration. Local priests claim it as the only pre-sultanate temple in Delhi still in use. Come on an ordinary day rather than during Navratri, when the congregation is large, and walk out to the Anangtal Baoli beside it, closed in by trees.