Around 1760, Daniel Boone reached an understanding with Richard Henderson for the exploration and preparation of the wilderness beyond the Appalachian Mountains, so that it may be more easily settled by those who sought to move westward.: Boone made an expedition in 1767 into the area of modern-day Prestonsburg, Kentucky,: and then in 1769, he set out with five others on an extended expedition through the Cumberland Gap and into Kentucky, where he stayed until March 1771.: Boone set out on a failed attempt at settlement in 1773, and then again in 1774, where he served as an officer in Lord Dunmore's War.: