After an illness lasting several months, thought to be tuberculosis, he died on 28 July 1840 in Cowes, Isle of Wight. On 3 August, his body was taken in his own yacht to Sunderland, then in a steamship to Lambton Castle. His funeral took place on 10 August, and was attended by over 300 Freemasons; they wanted to perform a Masonic ceremony for the occasion, but were asked not to do so by Durham's family. The ceremony began at the castle, where the Earl lay in state in the dining room. A procession, consisting of around 450 people in carriages and hundreds more on foot, then conveyed the body to the parish church of St Mary and St Cuthbert, Chester-le-Street, where Durham was buried in his family vault. A large crowd gathered to observe the procession; its size has been estimated as between 30,000 and 50,000 people. The Marquess of Londonderry, a political opponent of Durham's, travelled from London to act as a pallbearer at the funeral.