The largest of Huntingdon County's ironmasters' houses was built by John Lyon, who began investing in charcoal iron furnaces in 1813 and whose empire eventually stretched across western Pennsylvania to a rolling mill in Pittsburgh. He became wealthy enough to build this twenty-eight-room limestone house in a style befitting a Pennsylvania gentleman. Though the Georgian facade, with a full raised basement, has the appropriate symmetry, the provincial builder's technique is revealed by the awkward size and junction of the rear ell: a slab of building seventy feet long with ranks of windows and a flat roof attached to the north elevation. A full two-story porch was added to the facade when it was used as the Fairbrook Country Club, c. 1910. Many clues to its earliest existence remain on the grounds, including a four-hole privy, the remains of the iron furnace, several farm outbuildings, and five or six workers' houses. The complex straddles the border with Centre County and many of its structures are over the county line, but since it has always been taxed in Huntingdon County, it is included here. John Lyon's daughter's frame Greek Revival house built by carpenter George Washington Reynolds is just over the border in Centre County (1858; 5190 W. Whitehall Road).