 The use of piers of rectangular plan to support arcades was common, as at Mainz Cathedral and St Gertrude Nivelle, and remained usual in smaller churches across Europe, with the arcades often taking the form of openings through the surface of a wall.In Italy, where there was a strong tradition of using marble columns, complete with capital, base and abacus, this remained prevalent, often reusing existent ancient columns, as at San Miniato al Monte.A number of 11th-century churches have naves distinguished by huge circular columns with no clerestory, or a very small one as at St Philibert, Tournus.