On Thursday December 12, 1799, Washington spent several hours inspecting his farms on horseback, in snow, hail and freezing rain - later that evening eating his supper without changing from his wet clothes. Friday morning, he awoke with a severe sore throat (either quinsy or acute epiglottitis) and became increasingly hoarse as the day progressed. Sometime around 3 am that Saturday morning, he awoke his wife and said he felt ill. The illness progressed until Washington's death at home around 10 pm on Saturday December 14, 1799, aged 67. His last words were "'Tis well."
Throughout the world, men and women were saddened by Washington's death. Napoleon ordered ten days of mourning throughout France; in the United States, thousands wore mourning clothes for months.To protect their privacy, Martha Washington burned the correspondence between her husband and herself following his death. Only three letters between the couple have survived. Washington's tomb at Mount Vernon, Virginia On December 18, 1799, a funeral was held at Mount Vernon, where his body was interred.
Congress passed a joint resolution to construct a marble monument in the United States Capitol for his body, supported by Martha. In December 1800, the United States House passed an appropriations bill for $200,000 to build the mausoleum, which was to be a pyramid that had a base 100 feet (30 m) square. Southern opposition to the plan defeated the measure because they felt it was best to have his body remain at Mount Vernon.
In 1831, for the centennial of his birth, a new tomb was constructed to receive his remains. That year, an attempt was made to steal the body of Washington, but proved to be unsuccessful. Despite this, a joint Congressional committee in early 1832 debated the removal of Washington's body from Mount Vernon to a crypt in the Capitol, built by Charles Bulfinch in the 1820s. Yet again, Southern opposition proved very intense, antagonized by an ever-growing rift between North and South. Congressman Wiley Thompson of Georgia expressed the fear of Southerners when he said:
Remove the remains of our venerated Washington from their association with the remains of his consort and his ancestors, from Mount Vernon and from his native State, and deposit them in this capitol, and then let a severance of the Union occur, and behold the remains of Washington on a shore foreign to his native soil.
This ended any talk of the movement of his remains, and he was moved to the new tomb that was constructed there on October 7, 1837, presented by John Struthers of Philadelphia. After the ceremony, the inner vault's door was closed and the key was thrown into the Potomac.
source: Wikipedia