The Seneca nation, a group of indigenous Iroquoian speaking people native to North America, once called the region home prior to the inhabitation of Europeans. During the French and Indian War, Mary Jemison, a Scottish-Irish immigrant pioneer, was captured at the age of 12 from central Pennsylvania by a French and Shawnee raiding party. She was soon adopted by a family of Seneca people and eventually lived in western New York on the Genesee. She became assimilated into the Seneca nation, having seven children with two successive husbands. Her remains were later exhumed from the Buffalo Creek Reservation and reinterred on the grounds of a Seneca Council House (later relocated to the grounds of Letchworth in 1872).
The Seneca people were largely forced out after the American Revolutionary War.
Industrialist William Pryor Letchworth, who was involved in the malleable iron industry, began purchasing land near Middle Falls in 1859 after he fell in love with the Genesee River gorge that the Seneca once called Sehgahunda, or the “vale of the three falls.” By acquiring his initial acreage, Letchworth halted plans to install a hydroelectric dam in the gorge that would have diminished flows over the waterfalls.
Letchworth soon after began construction of Glen Iris and hired noted landscape architect William Webster to design the grounds of the estate, which included small ponds, rustic bridges, winding trails and roadways, and a fountain. In part to deter commercial enterprises from damaging the fragile nature of the gorge, he bequeathed his 1,000-acre property to the state of New York in 1906 to become a part of the newly created Letchworth State Park.
Letchworth’s residence was restored into the Glen Iris Inn. The boutique hotel, which includes a restaurant, boasts views of Middle Falls. His extensive collections were donated to the on-site William Pryor Letchworth Museum. The exhibits focus on the natural and cultural history of the Genesee Valley, and include archaeological artifacts of the Seneca nation, and displays on Mary Jemison, early pioneers, William Pryor Letchworth and the Genesee Valley Canal.
At the southern reaches of the state park is the Portage Viaduct, an iron railroad bridge that was completed in 1875. At 820 feet high, it is one of the highest railroad crossings in the United States. At the northern end of Letchworth is the Mount Morris Dam. Construction began in 1948 with the new dam opening in 1954. Designed to control flooding in Rochester downstream, the Mount Morris Dam is the largest flood control device of its kind east of the Mississippi.