The present disclosure relates to a coolant circuit (1) for a multi-cylinder internal combustion engine (3). The coolant circuit (1) having a plurality of coolant passages (10-1, 10-2, 10-3). A coolant distribution chamber (11) is provided in the coolant circuit (1). The coolant distribution chamber (11) has opposing first and second walls (12, 13) and a sidewall (14) extending between said first and second walls (12, 13). A coolant inlet (15) is disposed in the first wall (12) and a plurality of coolant outlets (17-1, 17-2, 17-3) are disposed in the sidewall (14). The coolant outlets (17-1, 17-2, 17-3) are each connected to a respective one of said coolant passages (10-1, 10-2, 10-3). A guide (18) is disposed in the coolant distribution chamber (11) for guiding coolant introduced into the coolant distribution chamber (11) through the coolant inlet (15) outwardly towards said coolant outlets (17-1, 17-2, 17-3). The coolant distribution chamber (11) may comprise a toroidal chamber. The present disclosure also relates to an internal combustion engine (3) and a cylinder head (2) comprising a coolant circuit (1). The present disclosure also relates to a vehicle (4).