Mount Holly is a township that is the county seat of Burlington County in the U.S. state of New Jersey. It is an eastern suburb of Philadelphia, the nation's sixth largest city as of 2020. As of the 2020 United States census, the township's population was 9,981, The township, and all of Burlington County, is a part of the Philadelphia-Reading-Camden combined statistical area and the Delaware Valley.
What is now Mount Holly was originally formed as Northampton on November 6, 1688. Northampton was incorporated as one of New Jersey's initial group of 104 townships created by an act of the New Jersey Legislature on February 21, 1798. Portions of the township were taken to form Little Egg Harbor Township (February 13, 1740, now part of Ocean County), Washington Township (November 19, 1802), Pemberton borough (December 15, 1826), Coaxen Township (March 10, 1845, now known as Southampton Township), Pemberton Township (March 10, 1846), Westampton Township (March 6, 1850) and Lumberton Township (March 14, 1860). There had been a Mount Holly post office since before the 1870 U.S. Census. The township was renamed Mount Holly as of November 6, 1931, based on the results of a referendum held three days earlier. The township was named for the prominent hill just north of downtown partially covered with holly trees. Some areas of today's Mount Holly were known as Bridgetown.
History
Colonial era
The first European settlement in what is now Mount Holly began in 1677 when Walter Reeves colonized the land from the Lenape (Delaware) Native Americans living in the area. He constructed a dam on Rancocas Creek to channel water through a raceway to power a gristmill and sawmill. Edward Gaskill and his sons dug the mill race on their property between 1720 and 1723. After the mills were established, more settlers were attracted to the area and built houses and commercial buildings on High, Church, White, Mill, and Pine streets, including the Shinn Curtis Log House (1712). By 1800, over 250 dwellings had been built.
Today no mills remain on the raceway, which still flows in its original course from the Rancocas just above the dam. The raceway proved a way for herring to make their way above the dam and was the scene of an annual fish run in the spring, which provided fresh herring for salting and eating. The former mill land has been preserved as the Mill Dam Park. It marks the importance of mills to the early settlements.
Revolutionary War
On December 17, 1776, Colonel Samuel Griffin of the Continental Army crossed the Delaware River with 600 men, mostly untrained men and boys with little equipment, who marched to Mount Holly where they set up a few 3-pounder artillery pieces on Iron Works Hill. Hessian commanders von Block and Carl von Donop were told that there were 3,000 American troops at Mount Holly.
By December 23, 1776, 2,000 Hessians were moved from Bordentown and positioned at The Mount in Mount Holly, where they engaged in a three-day-long artillery exchange, known as the Battle of Iron Works Hill or Battle of Mount Holly, with the Americans on Iron Works Hill. The Americans slipped away that night.
After George Washington crossed the Delaware River on December 25, 1776, the fact that thousands of Hessian troops had been drawn to Mount Holly aided in the Continental Army's success in the Battle of Trenton the next day, a surprising American victory that helped turn the Army's fading morale after the disastrous defeat at the Battle of Fort Washington just weeks before and the ignominious retreat through New Jersey.
19th century
The 1793 state legislature approved the relocation of the Burlington County seat from Burlington City to Mount Holly, which was approved by voters in a 1796 referendum. Several important municipal buildings were constructed, including the courthouse in 1796 and the county prison built . The Burlington County Prison was designed by Robert Mills, a nationally known architect who designed the Washington Monument. The town has numerous 18th and 19th-century buildings, most of which are included in the Mount Holly Historic District. Commercial buildings were constructed primarily along High Street.
In 1849, the Burlington and Mount Holly Railroad was established, connecting communities along the Delaware River to Philadelphia, the major city of the area. The railroad supported industrialization along its route. The Camden and Mount Holly Railroad constructed a station 20 years later near the intersection of Washington and King streets.
20th century
A trolley station was built in 1904 for passengers making connections to Burlington City and Moorestown. New municipal buildings were constructed during the 20th century, including the Town Hall on Washington Street (1930) and the U.S. Post Office (1935) located across the street (1935), both federally funded and constructed as Works Progress Administration projects under President Franklin D. Roosevelt during the Great Depression.
In the late 1950s, Mount Holly began to have economic difficulties due to industrial restructuring and the loss of working-class jobs. In the post-World War II period, numerous blue collar, family wage jobs disappeared as the community's traditional employers, the mills and dye factories, were shut down. At first, these job losses were offset in part by gains at the nearby military bases, Fort Dix and McGuire Air Force Base, especially during the Vietnam War. In 1970, the residential vacancy rate in Mount Holly was 4.3%.
By 1980, however, the vacancy rate had climbed to 8.7% as a result of the nearby military installations' downsizing after the end of the Vietnam War. During this same period, 1970–1980, shopping malls proliferated in the suburban Philadelphia area, and retail business in Mount Holly suffered.
Historic district
The Mount Holly Historic District is a historic district encompassing downtown Mount Holly. It was added to the National Register of Historic Places on February 20, 1973, for its significance in architecture, education, landscape architecture, politics/government, and transportation. The district includes 39 contributing buildings. The individually listed Old Schoolhouse, also known as the Brainerd School, was built in 1759 and contributes to the district. The Burlington County Prison is also listed individually and was listed as a National Historic Landmark in 1986. The Burlington County Courthouse was designed by architect Samuel Lewis and constructed by Michael Rush in 1796.
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File:Historic American Buildings Survey Nathaniel R. Ewan, Photographer March 15, 1936 SOUTHEAST ELEVATION - Burlington County Courthouse, High Street, Mount Holly, Burlington County, HABS NJ,3-MOUHO,1-1.tif|Burlington County Courthouse, HABS photo, 1936
File:Burlington County Prison, 128 High Street, Mount Holly (Burlington County, New Jersey).jpg|Burlington County Prison, HABS photo, 1938
File:Historic American Buildings Survey Nathaniel R. Ewan, Photographer March 29, 1937 EXTERIOR - NORTH ELEVATION - Three Tun Tavern, Mount Holly, Burlington County, NJ HABS NJ,3-MOUHO,6-1.tif|Three Tun Tavern, HABS photo, 1937
File:Historic American Buildings Survey Nathaniel R. Ewan, Photographer March 6, 1937 EXTERIOR - SOUTH ELEVATION - Stephen Girard House, Mount Holly, Burlington County, NJ HABS NJ,3-MOUHO,7-1.tif|Stephen Girard House, HABS photo, 1937
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Geography
According to the U.S. Census Bureau, the township had a total area of 2.87 square miles (7.43 km<sup>2</sup>), including 2.82 square miles (7.31 km<sup>2</sup>) of land and 0.05 square miles (0.12 km<sup>2</sup>) of water (1.60%). Clermont is an unincorporated community located within Mount Holly Township.