King's College Chapel is one of the great late-Gothic buildings in Europe. Henry VI began it in 1446, intending it as the spiritual heart of his new college; work continued intermittently for 70 years through royal wars and changes of regime until Henry VIII finally completed it in 1515. The result is a single soaring space — 88 metres long, 12 metres wide, 24 metres high — covered by the largest fan vault in the world, a breathtaking web of stone tracery that appears to defy gravity.
The stained glass, installed largely between 1515 and 1547, fills 26 vast windows and is among the finest Renaissance glazing in northern Europe. Rubens' Adoration of the Magi hangs over the altar. But the defining Cambridge experience connected to this building is the Festival of Nine Lessons and Carols, broadcast live on Christmas Eve from here around the world every year since 1928 — you can queue for unreserved seats, but expect to arrive very early. The chapel choir performs evensong during term time, and attending one of these services is free and worth doing. Admission is charged to the chapel itself during the day.