This lighthouse, which has stood overlooking the mouth of the Gironde estuary for centuries, towers 67.5m above the water. The Renaissance-style structure boasts several storeys separated from the traditional top of the building by a balustrade. On the ground floor, a monumental door leads to the 311 steps which climb up to the light itself. The first floor is home to the "king's apartment", while the second floor houses a chapel crowned with a fine dome.