Port Henry is a hamlet (and census-designated place) in Essex County, New York, United States.

[3] Port Henry lies on the eastern side of the town of Moriah and is approximately one hour's drive (52 miles or 84 km)[4] south of Plattsburgh.

A blast furnace constructed in 1822 in Port Henry was one of the first in the United States, and Republic Steel established major operations in the county.

The village residents used Lake Champlain and the Hudson River to transport its ore and products to major markets such as Albany and New York City.

By the end of the 19th century, residents harvested smelt from the lake for the restaurant trade, by ice fishing.

The Delaware & Hudson Railroad Depot, Moriah Town Office Building, Mount Moriah Presbyterian Church, Port Henry Fire Department Building, Sherman Free Library, and Van Ornam & Murdock Block are listed on the National Register of Historic Places.

[7] The Essex County Republication was published in Port Henry in the 19th and early 20th centuries, after which it moved to Keeseville.

The village is on the western shore of Lake Champlain at the northern end of Bulwagga Bay and is in the Adirondack Park.

Amtrak, the national passenger rail system, provides service to Port Henry, operating its Adirondack daily in both directions between Montreal, Canada and New York City.

A few miles south of Port Henry, the Champlain Bridge was built in 1929, connecting Crown Point to Vermont.