Williamsport is a town in Washington Township, Warren County, Indiana, United States.

[6] Williamsport was platted by (and named for) William Harrison on December 11, 1828,[7] on the south end of the eastern fractional part of the northeast quarter of section 11, township 21, range 8.

Harrison was the first to occupy the town in the fall of 1828; he built a log house at the east end of Main Street near the river and operated a ferry crossing there for several years.

[9] James Frank Hanly, who was the Governor of Indiana from 1905 to 1909, lived and practiced law here from 1879 to 1896; he is buried at Hillside Cemetery, on the northeast side of town.

[11] The Williamsport Presbyterian Church at 15 Fall Street, built in 1889, appears on the Indiana Register of Historic Sites and Structures.

It was closed in 1964 and stood vacant until 1991, when a non-profit corporation was set up to support the restoration effort.

[12] The Warren County Courthouse at 125 North Monroe Street was built in 1907-1908 and is on the United States National Register of Historic Places.

[13] Williamsport is located along State Road 28 near the shores of the Wabash River which forms the eastern border of the county.

Its most striking natural feature is Williamsport Falls, a 90-foot waterfall near the center of town and Indiana's tallest.

[24] These are important local employers, as 9.8% of Warren County's jobs relate to health care and social services.