The Piliers de Tutelle are the remains of a Roman temple or sanctuary from the 1st century AD — a row of marble columns that was discovered when the quartier around the Grand Théâtre was redeveloped in the 18th century. They were documented and partially preserved, and today stand in a courtyard behind the Grand Théâtre, visible through an iron gate.
They are minor ruins — a few columns, not a full site — but their presence a few metres from one of France's finest neoclassical opera houses is pleasingly unexpected. Roman Burdigala and 18th-century Bordeaux standing next to each other with two thousand years between them. The gate is usually open during the day.