Old door, Palais des Papes (Palace of the Popes), Avignon, France.
The Palais des Papes is the largest Gothic palace in the world. There are 15,000 square meters of living space, which is the equivalent of 4 Gothic cathedrals. Its construction began in AD 1252 and it became the residence of the Popes in 1309. The huge structure is actually two palaces joined together, each built for a different pope. The palace was seized and sacked by revolutionary forces during the French Revolution in 1789 so most rooms are totally empty, but some beautiful frescos were preserved.
The Courtyard (the old door can be seen on the far right).
The Palais de Papes external view. Detail of the main entrance and towers.