Palais du Tau, Angers, Episcopal palace in Angers, France

The Palais du Tau in Angers is a former episcopal residence next to Saint Maurice Cathedral with a distinctive T-shaped plan combining alternating brick and stone elements. The structure contains historical halls, a library, and various architectural features spanning different building periods.

An episcopal palace is documented north of the cathedral from the mid-9th century; the present building dates from the early 12th century. Bishop Ulger, impressed by the Tau hall of the Reims archbishopric at the 1131 council, rebuilt his residence on a T plan. Hardouin de Bueil altered the roofs in 1438, and Charles Joly-Leterme restored the complex in the second half of the 19th century, adding a new wing between 1861 and 1864.

The name comes from the T-shaped plan, tau being the Greek letter T; only the archiepiscopal palaces of Reims and Angers share it. Bishop Ulger borrowed the layout from Reims in 1131. Latin inscriptions from the 13th and 14th centuries survive, including one comparing clerics and knights and another where the building says it gives its honey freely and uses its sting only when forced.

The palace is entered from the rue de l'Oisellerie side, where a second entrance courtyard was formed by a wing built between 1861 and 1864; the main stair on the cour d'honneur, begun in 1506, was only completed up to the synod hall in 1864. The building now serves as the diocesan house of works, so the historic rooms are not a museum open to visitors.

The palace basement contains remains of a circular medieval kitchen, a rare architectural feature found in few places. At this same location, parts of an even older Roman city wall are still visible.