The last of the great Mughal imperial mosques is also the widest: a red sandstone courtyard that holds a hundred thousand worshippers, closed at the far end by three white marble domes and pinned at the corners by fifty-five-metre minarets. It went up in just two years, in 1673, and the gap between that haste and the result is startling. It faces the Lahore Fort across an open square that is, at dusk, one of the finest spaces in the subcontinent.