Monkwearmouth Colliery (or Wearmouth Colliery) was a major North Sea coal mine located on the north bank of the River Wear,located in Sunderland. It was the largest mine in Sunderland and one of the most important in County Durham in northeast England. First opened in 1835 and in spite of the many accidents at the pit, the mine was the last to remain operating in the County Durham Coalfield. The last shift left the pit on December 10, 1993, ending over 800 years of commercial coal mining in the region. The Colliery site was cleared a few years later, and the Stadium of Light, the football ground for Sunderland AFC, was built over it.