Patterson Viaduct

Ilchester is an unincorporated community and census-designated place in Howard County, Maryland, United States. The population was 23,476 at the 2010 census. It was named after the village of Ilchester in the English county of Somerset.

St. Marys College was a Roman Catholic school in Ilchester, Maryland (Illchester Mills) near modern Ellicott City, Maryland in Howard County. The ruins are near Ilchester and Bonnie Branch roads. The upper college building was built in 1868 consisting of a cupola topped eighteen bay by five bay building with a five by five bay projection. A three by three bay, five story "L" shaped addition is included, with all of the structure on a stone foundation. A three-story chapel was attached to the building in 1882. In 1934 a fifth floor was added throughout. A statue of Madonna with Child was situated in a niche.

Thistle Manufacturing Company factory was a historic factory located along the Patapsco River, which runs through Catonsville, Maryland across from Ilchester, Maryland. The 1800s factory was in continuous operation until 2003.

Bloede's Dam was a hydroelectric dam on the Patapsco River in Maryland. Built in 1906, it was the first submerged hydroelectric plant—that is, the power plant was housed under the spillway. It was also one of the earliest dams constructed of reinforced concrete. The dam was demolished in 2018 and its site is now part of Patapsco Valley State Park Avalon Area.

The Wilderness is a historic home located near Catonsville, Baltimore County, Maryland. It is a large stone and frame house located in a wooded setting west of Catonsville. The original home was built about 1800, and it attained its current appearance following a major expansion in 1899–1900, when it was a summer residence of Francis Cumberland Dugan II (1830-1914). It features multiple roof and dormer shapes and a wraparound porch reminiscent of the Queen Anne style. The third story is located within a tall mansard roof. Also on the property are a stone springhouse / smokehouse, a summer kitchen, log tenant house, and a large frame barn.The house was listed on the National Register of Historic Places in 1985.

Bethesda is located in Ellicott City, Maryland within Howard County, Maryland, United States. The home is sometimes mistakenly referred to as "Dower House" because a small dower house exists on the property. A "dower" is a widow's share for life of her husband's estate, so a dower house is where a widowed mother would live when her son and his family inherited and moved into the main house. The foundation of the original house was found using ground penetrating radar to the west of the existing structure. The center portion of the existing house is the oldest; dendrochronology revealed that the trees for the wood in that portion of the house were felled the winter of 1827–1828. Dendrochronology also revealed that the large granite section of the house to the west was added in 1841. The east section was added in 1960 by owner John M. DeBoy. While the house looks wide from the street, it is only one room deep. Outbuildings include a smoke house, a carriage house, and the stone "Dower House" which may have been built in the early 1830s to serve as a summer kitchen. Bethesda rests on a collection of surveyed properties totaling 1000 acres named "Long Reach", "Chews Resolution Manor", "Search Enlarged", "Search", and "Dorsey's Search" (448 Acres). The land grant was given to Maj Edward Dorsey (1646–1705) in 1682. When Edward Dorsey died, he willed the land to his nephew, Caleb Dorsey of "Belmont" in Elkridge, Maryland. Caleb gave the land to his daughter, Mary, when she married Michael Pue, an Irish doctor. They are the first people known to live on the property, and they lived there in 1790 when the newly formed United States of America conducted its first tax assessment. In 1769, the "Bethesda Old Place Farm" home was expanded on the property and run as a tobacco-producing plantation with 26 slave workers. Two successive generations of Pues also lived there. The property was struck by a tornado in 1858, and stayed in the Pue family until 1859. It was purchased by Thomas Lishear, a sea captain. He had three daughters who never married, and they lived in the house until their deaths. The house was later owned by Dr. George B. Sybert. By 1943, the property had been subdivided to 237 remaining acres. In 1954, the Columbia Hills Corporation developed the land leaving just 8.3 acres surrounding the house. By 1965, the land was subdivided down to three acres. Howard Research and Development purchased most of the original Long Reach property between 1963 and 1966 for the development of Columbia.

The Patapsco Swinging Bridge is located in the Avalon/Orange Grove area of Patapsco Valley State Park in central Maryland, United States. It is a suspension bridge consisting of a wooden deck supported by large cables. The Patapsco Valley has a history of "swinging" bridges built for pedestrian travel from one side of the river to the other. The Orange Grove Flour Mill was one such popular crossing and is where the current bridge now stands. The first bridge was built by the Orange Grove Flour Mill for employees to cross the river. The new swinging bridge, built by the Maryland Department of Natural Resources, is one of the most well known and most popular attractions at the Patapsco Valley State Park.

The Orange Grove Flour Mill was a flour mill established in 1856. It was one of the leading flour mills in the Mid-Atlantic states until it was destroyed in a fire in 1905.

Orange Grove was a town straddling the Patapsco river in Howard County and Baltimore County Maryland, United States The Orange Grove area was the site of two parallel roads running along the Patapsco river settled by the Elliotts in 1762. The road to then North was referred to as "George Washington's Gun Road" as the path of General Lafayette's troops en route to the battle of Yorktown. In 1856, the land was sold by George Elliot for $9,000 to George Worthington and George Baily. They started a construction of a six story mill and sold the property to C.A Gambrill for $45,000. The Gamrill Mill was renamed to Orange Grove producing "Patpasco Superlative Patent" and "Orange Grove" flour. Citizens lived on the Howard County side, using a rope bridge to travel to the mill and B&O railroad siding. In 1869, the mill was purchased by R.G. and P.H. MacGill keeping the name C.A. Gambill & Company, who added steam power in 1873 and modern rollers in 1879. In 1898, the Orange Grove school opened. In 1904, ice stacked up, tearing down the bridge. The same year, the company owned Phoenix mill burned in the great Baltimore fire. On 6 May 1905, the mill and train station burned in a fire started in the engine room monitored by George W. Carr. The town did not recover, and the ruins are part of the Patapsco State Park with a modern suspended bridge along the trail.

The Historical Ellicott City/Baltimore Trolley Line #9 Trail is a 1.25-mile (2.0 km) trail in western Baltimore County, Maryland. It begins at the west end of Edmondson Avenue and extends from Catonsville through Oella to Main Street, Ellicott City. The trail follows what was originally part of the Catonsville and Ellicott City Electric Railway Company trolley line that shuttled passengers between Ellicott City and Baltimore from the late 1890s to the mid-1950s.

Summit is a historic home located in Catonsville, Baltimore County, Maryland. It a large brick house, once part of a country estate owned by James Albert Gary. It features a three-story Italianate tower and large wing extending to the rear. The main façade is three stories and five bays wide, with the tower located on the east side. A one-story porch with square columns and railings runs across the full façade. The mansion was built originally as a summer home and later converted to apartments after its sale to the Summit Park Company in 1919.It was listed on the National Register of Historic Places in 1979.

Sheppard Pratt at Ellicott City was a private psychiatric hospital located in Ellicott City, Maryland. It had a 20-bed adult unit, an 18-bed co-occurring disorders unit, an 18-bed crisis stabilization unit, a 22-bed adolescent unit, and an adult day hospital. The hospital was owned and operated by the Towson, Maryland based Sheppard Pratt Health System Prior to its purchase by Sheppard Pratt the facility was known as Taylor Manor, one of only a dozen privately owned psychiatric facilities in the nation. The hospital closed with the opening of Sheppard Pratt at Elkridge in 2020. Most of the original structures were already demolished prior to the campus closure, as new plans for the Taylor Highlands development were already underway.