Western Maryland is the portion of the U.S. state of Maryland that traditionally consists of Washington, Allegany, and Garrett counties. Frederick County is also sometimes included, despite being part of the Washington, D.C. metropolitan area. The region is bounded by the Mason-Dixon line to the north, Preston County, West Virginia to the west, and the Potomac River to the south. There is dispute over the eastern boundary of Western Maryland. For most residents of the Baltimore-Washington area, everything west of Frederick city is considered Western Maryland. However, the people of the more mountainous and isolated Allegany County and Garrett County consider Sideling Hill the boundary between Western Maryland and what they refer to as "down-state." According to the Census Bureau's 2007 dataset, Western Maryland (including Washington and Frederick counties) has a population of 472,039, accounting for 8.4% of the population of Maryland. Its land area is 2,194.39 square miles (5,683.4 km2), or 22.45% percent of the state's land area. Only 21.7% of Western Maryland's residents live in the geographically isolated Allegany and Garrett counties; the other 78.3% live in suburban Frederick and Washington counties.
Western Maryland is much more rural than the Baltimore-Washington Metropolitan Area, where most of the state's population lives; even Frederick and Washington counties are less urbanized than places closer to Washington, D.C. and Baltimore. Many people still perform a variety of subsistence agriculture for their food needs, and there are relatively few towns larger than 10,000 people. Western Maryland is noted for its idyllic rural landscapes in its eastern portion and the mountainous terrain in Allegany and Garrett Counties. The area is generally regarded as part of Appalachia, with the extreme western section having more of an affinity to Pittsburgh than the rest of the state. Washington, Allegany, and Garrett Counties are part of the Appalachian Regional Commission. Garrett County, the state's westernmost county, largely aligns itself through marketing and sports with West Virginia and the Pittsburgh area rather than Maryland.
The climate of cities west of Frederick is more akin to the mountains of northernWest Virginia than to any other part of Maryland. Summers tend to be much cooler than in the rest of the state, and winters harsher. Temperatures in winter often drop to near or below 0 F (-18°C), and snowfall averages from 20 inches farther east to over 120 inches in the higher elevations. Comparably, Prince George's County, in the eastern part of the Washington, D.C. area, averages only 25 inches of snow and wintertime temperatures many times exceed 50 F (10°C).
Western Maryland has a heavily agricultural economy. Its best-known crops are the apples grown in the Cumberland Valley, but corn, potatoes, beans, and varieties of green-leaf vegetables are grown as well. Mixed crop and livestock farms are common, and the region has a large number of dairy cattle farms. There is however, a thriving tourist industry, and places such as Deep Creek Lake in Garrett County are frequented by many visitors every year. Garrett County is also well known for its numerous state parks and outdoor activities. Maryland's only ski resort, Wisp Ski Resort, is located in Garrett County near Oakland.