Barking Abbey is a former royal monastery located in Barking, in the London Borough of Barking and Dagenham. It has been described as having been "one of the most important nunneries in the country". Originally established in the 7th century, from the late 10th century the abbey followed the Rule of St. Benedict. The abbey had a large endowment and sizeable income but suffered severely after 1377, when the River Thames flooded around 720 acres (290 ha) of the abbey's land, which was unable to be reclaimed. Despite this, at the time of the dissolution it was still the third wealthiest nunnery in England.