Frederick County, Maryland in the context of Maryland Route 355

The Province of Maryland was an English and later British colony in North America from 1634 until 1776, when the province was one of the Thirteen Colonies that joined in supporting the American Revolution against Great Britain. In 1781, Maryland was the 13th signatory to the Articles of Confederation. The province's first settlement and capital was in St. Mary's City, located at the southern end of St. Mary's County, a peninsula in the Chesapeake Bay bordered by four tidal rivers.

The province began in 1632 as the Maryland Palatinate, a proprietary palatinate granted to Cecil Calvert, 2nd Baron Baltimore, whose father, George, had long sought to found a colony in the New World to serve as a refuge for Catholics at the time of the European wars of religion. Palatines from the Holy Roman Empire also immigrated to Maryland, with many settling in Fredrick County, with Maryland Palatines (Palatine German: Marylandisch Pälzer) reaching a population of 50,000 by 1774.

Frederick is a city in and the county seat of Frederick County, Maryland, United States. Frederick's population was 78,171 people as of the 2020 census, making it the second-largest incorporated city in Maryland behind Baltimore. It is a part of the Washington metropolitan area and the greater Washington–Baltimore combined statistical area.

The city is located at an important crossroads at the intersection of a major north–south Native American trail and east–west routes to the Chesapeake Bay, both at Baltimore and what became Washington, D.C., and across the Appalachian Mountains to the Ohio River watershed.

Interstate 270 (I-270) is a 34.7-mile (55.8 km) auxiliary Interstate Highway in the U.S. state of Maryland that travels from I-495 (Capital Beltway) just north of Bethesda in Montgomery County north to I-70 in the city of Frederick in Frederick County. It consists of the 32.6-mile (52.5 km) mainline as well as a 2.1-mile (3.4 km) spur that provides access to and from southbound I-495. I-270 is known as the Washington National Pike, and makes up the easternmost stretch of the Dwight D. Eisenhower Highway. Most of the southern part of the route in Montgomery County passes through suburban areas around Rockville and Gaithersburg that are home to many biotech firms. This portion of I-270 is up to 12 lanes wide and consists of a local–express lane configuration as well as high-occupancy vehicle lanes (HOV lanes) that are in operation during peak travel times. North of the Gaithersburg area, the road continues through the northern part of Montgomery County, passing Germantown and Clarksburg as a six- to eight-lane highway with an HOV lane in the northbound direction only. North of here, I-270 continues through rural areas into Frederick County and toward the city of Frederick as a four-lane freeway.

The freeway was built between 1953 and 1960 as the Washington National Pike between Bethesda and Frederick and carried U.S. Route 240 (US 240), which was rerouted off what is now Maryland Route 355 (MD 355) between these two points. With the creation of the Interstate Highway System a few years later, the road was designated as I-70S along with US 240. There were plans to extend I-70S to I-95 in Washington, D.C., on the North Central Freeway from the Capital Beltway; however, they were canceled in the 1970s due to opposition from residents in the freeway's path. The concurrent US 240 designation was removed in 1972 and I-70S became I-270 in 1975. Increasing traffic levels led to a $200-million (equivalent to $509 million in 2024) widening of the road in Montgomery County to its current configuration. Many improvements are slated for I-270, including the widening of the route that would add high-occupancy toll lanes (HOT lanes).

Camp David is a 125-acre (51-hectare) country retreat for the president of the United States. It lies in the wooded hills of Catoctin Mountain Park, in Frederick County, Maryland, near the towns of Thurmont and Emmitsburg, about 62 miles (100 kilometers) north-northwest of the national capital city, Washington, D.C. It is code-named Naval Support Facility Thurmont. Technically a military installation, it is staffed primarily by the Seabees, the Civil Engineer Corps (CEC), the United States Navy, and the United States Marine Corps. Naval construction battalions are tasked with Camp David construction and send detachments as needed.

Originally known as Hi-Catoctin, Camp David was built as a retreat for federal government agents and their families by the Works Progress Administration. Construction started in 1935 and was completed in 1938. In 1942, President Franklin D. Roosevelt converted it to a presidential retreat and renamed it "Shangri-La", after the fictional Himalayan paradise. Camp David received its present name in 1953 from President Dwight D. Eisenhower, in honor of his father and his grandson, both named David.

Fox's Gap, also known as Fox Gap, is a wind gap in the South Mountain Range of the Blue Ridge Mountains, located in Frederick County and Washington County, Maryland. The gap is traversed by Reno Monument Road. The Appalachian Trail also crosses the gap along the ridgeline.