A multi-cylinder internal combustion engine with liquid cooling comprises a cylinder head and a cylinder crankcase connected with the cylinder head; the crankcase includes cylinder liners circumcirculated by the cooling medium. For reducing the weight of the internal combustion engine, the cooling medium quantity is reduced and the cylinder head and the cylinder liners are acted upon with cooling medium by a cross-flow cooling system. Additionally, an internal combustion engine unit of relatively short construction and relatively light weight is created by the particular construction of the cylinder liners.