In an internal combustion engine comprising a plurality of cylinders with at least one cylinder head including inlet channels extending from an inlet flange surface to a cylinder inlet and outlet channels extending from a cylinder outlet to an opening in an outlet flange surface and an oil chamber provided in the cylinder head for supplying lubricant to an actuation device for gas exchange valves, the inlet flange and the outlet flange have flat surfaces which are arranged at an angle relatively to each other so that the surface planes intersect above the cylinder head and the cylinder head, as a result, has an essentially triangular cross-section.