Seaton Sluice is a village in Northumberland. It lies on the coast at the mouth of the Seaton Burn (a small river), midway between Whitley Bay and Blyth. It has a population of about 3,000 people. Early history Seaton Sluice lies north of the village of Hartley, and was once part of it, being called Hartley Pans, because of the salt-pans used to harvest salt there from as far back as 1236. Hartley was once an area stretching from the Brier Dene Burn (in present-day Whitley Bay) to the Seaton Burn, which belonged to Tynemouth Priory. In 1100 the land became the property of the Hubert de Laval, nephew by marriage to William the Conqueror. The de Lavals (or Delavals) settled about inland from Hartley Pans and their place of residence became Seaton Delaval, the name 'Seaton' being derived from Old English meaning a settlement (ton) by the sea. Harbour improvements Before 1550 the salt produced at Hartley Pans had been transported to Blyth to be exported, but after that date it was shipped directly from the small, natural harbour. The village henceforth became known as Hartley Haven, and was used for the export of coal as well as salt. However the harbour was prone to silting, which limited access by ships. This problem was tackled by Sir Ralph Delaval (1622–1691), who had a pier constructed, and sluice gates that trapped the seawater at each high tide. At low tide the gates were opened, flushing the sand out of the harbour. Henceforth the village became known as Seaton Sluice. The harbour remained like this until the 1760s, when Sir John Hussey Delaval had a new entrance made for the harbour by blasting a channel through solid rock, providing what was known as 'The Cut', deep, wide and long. The new channel was opened in 1763 and, as a result, the land between the old harbour entrance and the new channel became an island, known as 'Rocky Island'. A footbridge connected the island to the mainland. The new channel could be sealed off at both ends to allow loading to continue no matter what the state of the tide. On the other side of the old channel, opposite Rocky Island, was a ballast hill known as Sandy Island, built up from the ballast of ships entering the harbour. The ballast hill and The Cut can still be seen. The new entrance