Bull Bay (Welsh: Porth Llechog) is a village on the northern coast of Anglesey, Wales. Its Welsh name, Porth Llechog, means "sheltered bay". The English name is derived from Pwll y Tarw ("the bull's pool"), which is located near the shore close to the bay.
The village is located on the A5025. It is the most northerly village in Wales and also contains Wales' most northerly golf course which was opened and funded by a local aristocrat in 1913. The island of East Mouse lies within the bay, the coastline of which is rocky and contains many caves. Some of these rocks are over 570 million years old which make them amongst the oldest in Wales.
Lowry refers to the golf course in his novel Ultramarine when Taff one of the crew of Oedipus Tyrannus says; "Amlwch I lived. I used to work in the forge near Bull Bay. I was a caddy on the links there for a time-" (Pg. 50)