Milecastle 4 (Westgate Road) was a milecastle of the Roman Hadrian's Wall. Its remains exist beneath the Newcastle Arts Centre at 67-75 Westgate Road. This position is some way away from its predicted position which is at these The actual location is between the predicted positions of Turrets 4A and 4B, which has led to suggestions that the numbering and positioning of milecastles and turrets on this part of Hadrian's Wall should be reconsidered.