MERCURE WHITE HART SALISBURY. . From London, M3, A303, A343, A30 ring road and follow the signs for the city centre. When you reach Salisbury, follow ring road south until you reach the roundabout on the north bank of the River Avon, then turn into Exeter Street towards the city centre . Continue along St John Street, go past the Cathedral on the left. The hotel is on the right hand side, opposite the Law Courts.