First State National Historical Park

New Castle is a city in New Castle County, Delaware, United States. The city is located six miles (10 km) south of Wilmington and is situated on the Delaware River. As of 2020, the city's population was 5,551. New Castle constitutes part of the Delaware Valley or Philadelphia metropolitan area.

The Hermitage was a historic home located at New Castle, New Castle County, Delaware. It was built between about 1700 and 1818, and consisted of three brick sections. The oldest section was the 2+1⁄2-story west wing. There was a two-story, rear kitchen wing, with servant's quarters above. The main section was built in 1818, and was a two-story, three-bay structure. It was built by U.S. Senator Nicholas Van Dyke (1770–1826) as a farm and summer retreat for his family.The house was added to the National Register of Historic Places in 1973.The Hermitage was heavily damaged by fire between 5:00 p.m. and 10:00 p.m. on February 18, 2007, in an act of arson. Following the fire, the two oldest sections of the house were completely destroyed, with only the walls left standing. The newer section (circa 1810) of the house was relatively intact, including a marble fireplace in the front, and a carved and gesso mantle and woodwork in the rear. Declared a safety hazard by the city of New Castle, the remains of the Hermitage were torn down in 2009. Nothing was salvaged.

Amstel House, also known as Dr. Finney House, is a preserved building in New Castle, Delaware, United States, built in the 1730s. The decline of New Castle in the 19th century meant that many owners of homes could no longer afford to make changes to them, which is why so many buildings were preserved. That changed, however, when New Castle was "rediscovered" during the Colonial Revival phase of the 1920s and 1930s and old buildings began to be torn down and replaced by new construction.In 1931, to protect New Castle's heritage, a group of concerned citizens raised funds to buy the Amstel House, which faced an uncertain fate. This was the town's first formal preservation effort. Shortly thereafter the group evolved into the New Castle Historical Society which, in the 75 years that have followed, has worked closely with the city and other civic organizations to save, preserve and restore many of the town's historic architectural treasures. It was listed on the National Register of Historic Places in 1977.

The Dutch House is a late-17th-century house in New Castle in the U.S. state of Delaware. Built during New Castle's colonial period, it is considered one of the oldest houses in the state. The house has been used for various purposes throughout its history, including as a rental property, storehouse, and historic house museum. The Dutch House is currently managed by the New Castle Historical Society.

Broad Dyke is an original dyke in the United States built by the Dutch in 1655 in New Castle, Delaware. It is the center of the twelve mile circle that forms the arc that marks the northern state line (between Delaware and Pennsylvania). It was surveyed in 1701 by Empson and Pusey.

Broad Creek Hundred is a hundred in Sussex County, Delaware, United States. Broad Creek Hundred was formed in 1775 from Somerset County, Maryland. Its primary community is Bethel.

Immanuel on the Green (Episcopal) is an historic church in New Castle, Delaware, listed as a contributing property in the New Castle Historic District. The church is situated near the center of New Castle at the northeast end of the Green, or town common, making it a prominent local landmark and tourist attraction. Operating continuously since 1689, it is the oldest Anglican parish in Delaware and the oldest continuously operating Anglican/Episcopal parish in the country. The church building was constructed between 1703 and 1708 and enlarged in 1822. The interior and roof were rebuilt following a disastrous fire in 1980.

The New Castle Court House Museum is the center of a circle with a 12-mile radius that defines most of the border between the states of Delaware and Pennsylvania and parts of the borders between Delaware and New Jersey and Maryland.It is one of the oldest courthouses in the United States and has played a role in a number of historic events. It was declared a National Historic Landmark in 1972. The building is also a contributing property to a second National Historic Landmark, the New Castle Historic District. It is part of First State National Historical Park.

New Castle Presbyterian Church is a Presbyterian Church (USA) congregation located in New Castle, Delaware which conducts worship services weekly within a historic meeting house, which was erected in 1707. It was founded as a Dutch Reformed Church in 1657 because a clergyman of that faith had accompanied Peter Stuyvesant when building Fort Casimir in 1651. The founding date of the congregation was marked by the arrival of the first permanent pastor for the congregation, Reverend Evardus Welius on August 21, 1657. By 1664, the British had taken control of the colony from the Dutch, leading to an increase in French Huguenot, English, and Scottish colonists taking residence within the town. Upon the arrival of Rev. John Wilson, as Scotsman, the church took on its distinctive Presbyterian form. Francis Makemie, Rev. John Wilson, and six other ministers met within Philadelphia in 1706 to organize the first Presbytery in the New World.

Lesley-Travers Mansion, also known as the Deemer House, Travers House, and Lesley House, is a historic home located at New Castle, New Castle County, Delaware. It was designed by noted Baltimore architects Thomas and James Dixon and built in 1855. It has a two-story, five-bay, brick core with several appendages and wings. It has a castle-like appearance, with a slate-covered steeply pitched gable roof and five-story tower, and is in the Gothic Revival style.It was added to the National Register of Historic Places in 1973.

The Read House & Gardens is a historic house museum at 42 The Strand in New Castle, Delaware. The house, built in 1797-1804 for George Read, Jr., was the largest and most sophisticated residence in the state at the time, and is a significant early example of high-style Federal period architecture. The adjacent formal gardens were laid out in the late 1840s by William Couper, the house's third owner. The property was designated a National Historic Landmark in 2016, and is part of the landmark New Castle Historic District. The house is now owned and operated by the Delaware Historical Society as a museum.

Battery Park is a public park in New Castle, Delaware bordered by West 3rd Street, Delaware Street and the Delaware River. The Separation Day celebration commemorating the political division of Delaware from Pennsylvania is held here in mid-June annually.