Heritage Open Day: Explore one of Bridlington’s oldest buildings. The Bayle is a Grade I listed building and Ancient Monument dating back to the 12th Century, housing the Bayle Museum, which features a collection of artefacts dedicated to the history of the local area. The Bayle has a rich and varied history. Archaeological surveys have concluded the original stonework dates to the 12th Century when it is originally thought to have been a gatehouse to a wooden palisade castle built by William Le Gros in 1143, although little information remains as to the further use of the building until the early 14th Century. In the 14th Century the Bayle Gate was adapted to become the Gatehouse to the Bridlington Priory; the ground floor of the then 2 storey building housed a Porter and an Almoner.