Triadelphia Reservoir

Hawlings River is a 12.9-mile-long (20.8 km) tributary of the Patuxent River in Montgomery County, Maryland. The watershed covers an area of about 28 square miles (73 km2). The waterway was originally called Holland's River. The headwaters of the river originate in the area north of Laytonsville, and the river flows southeast, entering the Patuxent about 1.5 miles (2.4 km) below the Triadelphia Reservoir. Portions of Hawlings River flow through Rachel Carson Conservation Park and Hawlings River Stream Valley Park. Tributaries of the Hawlings River include Mount Zion Tributary, Reddy Branch, Olney Mill Tributary, Gregg Tributary, and James Creek. The river and its tributaries total about 98 miles (158 km) of streams.Before 1769 local residents petitioned the colonial government to build a chapel on the river.

The Brookeville Woolen Mill and House is a historic home and woolen mill located in Brookeville, Maryland, in Montgomery County. The complex consists of two buildings constructed of rubble masonry. The woolen mill is a small one-story structure. South of the mill are two stone worker's houses, one of which is a three-by-two-bay, 1+1⁄2-story stone house. The house was most likely constructed prior to 1783. The complex may have been built by the Riggs family, who later became well-known bankers and merchants in Washington, D.C.It was listed on the National Register of Historic Places in 1978.

Montrose is a historic slave plantation located at Clarksville, Howard County, Maryland, United States. It was built in 1844 by Dr. William H. Hardey, prominent physician and secessionist in the American Civil War. One of Dr. Hardey's six children married John Randall, brother of James Ryder Randall, the author of "Maryland, My Maryland!" The house is basically a five-bay-wide, two-bay-deep, and 2+1⁄2-story stone structure with two dormers set into the gable roof on its south elevation and wide brick chimneys set into its east and west walls. A shingled 1+1⁄2-story cottage lies north of Montrose with barns and outbuildings lying northwest of them both.Montrose resides next to Huntington Farms, a house built by his brother John T. Hardey. The farm has been subdivided to 4.2 acres for residential construction, with the gravesite for the family and slaves located between two pipe-stem driveways for the development. Montrose was listed on the National Register of Historic Places in 2000.

Brinklow is an unincorporated community in Montgomery County, Maryland, United States. Brinklow is located on Maryland Route 650, 3 miles (4.8 km) northeast of Olney. Brinklow has a post office with ZIP code 20862. It is located within the Ashton-Sandy Spring census-designated place for statistical purposes. The community was named by Hallie Lea, a storekeeper in the late 1880s, most likely for Brinklow in Warwickshire, England.

Hickory Ridge or White Hall is an historic property located in Highland in Howard County, Maryland, United States. It is registered in the Maryland Inventory of Historic Properties. The 500-acre property known as Hickory Ridge was surveyed by Henry Ridgely III (1690–1749) ("Col. Henry Ridgely"), a grandson of pioneering surveyor Henry Ridgely (1640–1710) who had been granted land by George II of Great Britain. On Henry Ridgely III's death in 1749, the tract was deeded to his son Greenberry Ridgely (1726–1783), who built a stone cottage the same year, which still stands. In 1760 or 1789, Ridgely began building the Georgian architecture primary residence. The building is a two-and-a-half-story structure made of Flemish brick bond. The farm had enslaved labor who worked in fields of tobacco and wheat, and were housed in stone "Quarters". Greenberry Ridgely's son Nicholas Greenberry Ridgely (1764–1829), a rich wine merchant in Baltimore, inherited the property in 1800 and added on to the main house. The property was then acquired by the Adams family.Samuel and Martha Smith Hopkins acquired the property[from who?] in either the 1850s or 1877, naming it "White Hall" after the birthplace of Samuel, and his uncle the hospital/university founder Johns Hopkins. The Hopkins family lived there for 75 years. It is where Maryland State Senate President James A. Clark, Jr.'s mother Alda Hopkins was born and raised.It was sold[by who?] to Henry H. Owens who restored the "Hickory Ridge" name. The following owners Richard Jenkins and his wife restored the property to its historical character, beginning in 1972, and oversaw its inclusion in the Maryland Inventory of Historic Properties, in 1977. Jenkins sold the property in 1983 to John McDaniel, founder and Chief Executive Officer of MedStar Health (ret. 2006). "Since I've been there, we’ve hosted every governor," McDaniel said, who listed the property for sale in 2019.Horses have long been a tradition. Samuel Harold Hopkins, son of the Samuel Hopkins who bought the property, was a founder and former president of the racetrack in Laurel, Maryland. He held the Horse Show at Highland on the estate. John McDaniel was a longtime Maryland racing commissioner, and expanded the equestrian facilities to breed thoroughbreds.

Located Clarksville in Howard County, Maryland, United States, Huntington Farms. Huntington Farms is a two-story L-shaped brick house started in 1840 by John T. Hardey. Hardey's brother Dr. William H. Hardey, built Montrose next door in 1844. The house was built during the antebellum slavery period in the Howard District of Anne Arundel County, which later became Howard County. In 1875, the house was destroyed in a fire and rebuilt in its current configuration. The property contains remnants of a brick kiln that was used by slaves to fire bricks, and a graveyard that contains family and slaves. The graveyard containing Nicholas Hardy, buried in 1850 is now located between two pipe-stem driveways in the subdivision. The surrounding farmland has been reduced from 185 acres to 13 acres in 1977 and subdivided to only 3.085 acres around the original house for residential development.

Dayton is an unincorporated community located in Howard County, Maryland, United States. Dayton is located southwest of Baltimore and north of Washington, D.C., between Clarksville and Glenelg.

Brookeville is a town in Montgomery County, Maryland, located 20 km (12 mi) north of Washington, D.C., and 2 km (1.2 mi) north of Olney. Brookeville was settled by Quakers late in the 18th century and was formally incorporated as a town in 1808. Historically part of the local agricultural industry, Brookeville is now at the northern edge of the densely developed Washington suburbs. The population was 166 at the 2020 census.Brookeville is notable as the "United States Capital for a Day" during the War of 1812, when British troops burned Washington D.C., and President James Madison sought refuge in Brookeville on August 26, 1814. During the American Civil War, Brookeville, along with nearby Sandy Spring, was a stop on the Underground Railroad.

The Brookeville Academy is located in the heart of the Historic District in Brookeville, Maryland, a town located twenty miles (32 km) north of Washington, D.C., and two miles (3.2 km) north of Olney in northeastern Montgomery County, Maryland. It was built in 1810 as one of the first private schools in Montgomery County, Maryland. Now, fully restored, it serves as a unique community center suitable for meetings, social and cultural events. It is located in the Brookeville Historic District, which served as the "Capital for a Day" in 1814 when President Madison had to flee the White House during the British Invasion of the War of 1812.

The Brookeville Historic District is a national historic district located at Brookeville, Montgomery County, Maryland. It is located in the crossroads village of Brookeville, with almost all of the houses found along the two main streets, Market and High. The majority of the structures were built before 1900, and range in style from the Federal-style Jordan House to the simple, vernacular cabin known as the Blue House. The houses are built of stone, brick, and frame, and cover a period from 1779 to the 1950s. With the exception of the Post Office and plumbing shop, the town is a residential one. Of particular interest are the many outbuildings and the brick sidewalks.It was listed on the National Register of Historic Places in 1979.

Snell's Bridge is an historic bridge over the Patuxent River on the road between present-day Highland, Maryland and Ashton, Maryland. Farms surrounding the bridge were surveyed as early as 1720. In 1777, George Snell was considered the owner of the bridge by Montgomery County with George Darby listed as the road overseer. In November 1787, the State of Maryland funded a fifty-foot wide road to be built from Snell's Bridge and Greens Bridge upstream to Ellicott's Mills. Richard Green, Nathanial Owen, and John Ellicott were appointed commissioners for the project.The land next to the bridge is the birthplace of the Whig Major who ordered the Peggy Stuart burned.During the British invasion of the War of 1812, American troops led by William H. Winder retreated east across Snell's Bridge on August 26, 1814. The President stayed at Brookville, with the disorganized troops gathering at the bridge for the night. After camping overnight at the bridge, the General concluded that he should proceed directly to Baltimore in case the British were advancing northward leaving Brigadier General Stansbury in charge of the troops at camp. The British were at the same time leaving Washington, and boarded ships to sail the Potomac and Chesapeake toward Baltimore.In the 1840s, the state funded a replacement to Snell's Bridge.The modern bridge is a concrete arch built in 1928 along with the widening of route 108 in Howard County. The bridge replacement was funded via the 1920 Lateral and Post Roads Act. A historical survey was conducted in 1995 without mention of the bridge's role in the War of 1812.