In 1739, Whitefield returned to England to raise funds to establish the Bethesda Orphanage, which is the oldest extant charity in North America. On returning to North America in 1740, he preached a series of revivals that came to be known as the Great Awakening of 1740. In 1740 he engaged Moravian Brethren from Georgia to build an orphanage for Negro children on land he had bought in the Lehigh Valley of Pennsylvania. Following a theological disagreement, he dismissed them but was unable to complete the building, which the Moravians subsequently bought and completed. This now is the Whitefield House in the center of the Moravian settlement of Nazareth. He preached nearly every day for months to large crowds of sometimes several thousand people as he traveled throughout the colonies, especially New England. His journey on horseback from New York City to Charleston was the longest then undertaken in North America by a white man.