Garrett County is the westernmost county of the U.S. state of Maryland. Created from Allegany County, Maryland in 1872 it was the last Maryland county to be formed. As of the 2010 census, the population was 30,097. It was named for John Work Garrett (1820–1884), president of the Baltimore and Ohio Railroad. The county has long been part of the media market of Pittsburgh, Pennsylvania. It is considered to be a part of Western Maryland.
The Commonwealth of Pennsylvania is to the north. The Maryland–Pennsylvania boundary was surveyed and marked between April 1765 and October 1767 by astronomer Charles Mason and surveyor Jeremiah Dixon. This boundary is commonly known as the Mason-Dixon Line. The eastern border with Allegany County was defined by the Bauer Report, submitted to Governor Lloyd Lowndes, Jr. on November 9, 1898. The Potomac River and State of West Virginia lie to the south and west.
The Eastern Continental Divide runs along portions of Backbone Mountain. The western part of the county, drained by the Youghiogheny River, is the only part of Maryland within the Mississippi River drainage basin. All other parts of the county are in the Chesapeake Bay basin.
Garrett County contains over of parks, lakes, and publicly accessible forestland. Popular activities in the county include camping, hiking, backpacking, rock climbing, alpine and cross county skiing, snowmobiling, hunting, ice fishing, fly fishing, whitewater canoeing, kayaking, rafting, boating, swimming, sailing, horseback riding, and water skiing.
The National Register of Historic Places listings in Garrett County, Maryland has 20 National Register of Historic Places properties and districts, including Casselman Bridge, National Road a National Historic Landmark. Garrett County is part of Maryland's 6th congressional district and Oakland is the county seat.
In the early 20th century, the railroad and tourism started to decline. Coal mining and timber production continued at a much slower pace. Today, tourism has made a dramatic rebound in the county with logging and farming making up the greatest part of the economic base. Due to a cold climate and lack of any large city, Garrett County has remained a sparsely populated rural area.