Mendham Borough is a borough in southwestern Morris County, in the U.S. state of New Jersey.Explore Southwestern Morris County, Morris County Tourism Authority. Accessed April 10, 2024. "Southwestern Morris County includes a multitude of farms, farmers markets and community-supported agriculture offering fresh produce and festivals throughout the growing season throughout its communities of Mount Olive, Washington Township (Long Valley), Roxbury, Chester, Chester Township, Mount Arlington, Mendham, Mendham Township, Randolph and Netcong." As of the 2020 United States census, the borough's population was 4,981, unchanged from the 2010 census, which in turn reflected a decline of 116 (−2.3%) from the 5,097 counted in the 2000 census.Table 7. Population for the Counties and Municipalities in New Jersey: 1990, 2000 and 2010, New Jersey Department of Labor and Workforce Development, February 2011. Accessed May 1, 2023. Located in the Raritan Valley region within the New York metropolitan area, the North Branch of the Raritan River begins in Mendham Borough and flows in a southwest direction towards neighboring Somerset County.Raritan River North Branch (above/including India Brook) Subwatershed, Raritan Headwaters. Accessed July 3, 2018. "This subwatershed includes the headwaters of the North Branch Raritan River in Morris County. The North Branch of the Raritan River begins in the Borough and flows in a southwest direction."Raritan Basin Hydrology, New Jersey Water Supply Authority, June 2017. Accessed July 7, 2023.

Located on the northern end of the Somerset Hills region, the borough is known for its country homes and historic downtown."Review: New Jersey Country Homes The Somerset Hills." T3 Consortium, LLC, last modified September 2006, backed up by the Internet Archive as of July 24, 2008. Accessed December 11, 2015.

The Mendham Historic District was listed on the National Register of Historic Places and the state register in 1985.New Jersey and National Registers of Historic Places: Morris County, New Jersey Department of Environmental Protection Historic Preservation Office, updated June 22, 2023. Accessed July 7, 2023. Notable landmarks in the district include the Phoenix House, which serves as the borough's municipal building, along with the Black Horse Inn Tavern & Pub; New Jersey’s oldest continually operating restaurant, dating back to 1742.Black Horse Tavern & Pub, Morris County Tourism. Accessed July 7, 2023. "Drink and dine in a renovated 1740 stagecoach house at The Black Horse Tavern & Pub."Kelly, Joe. "New Jersey’s Oldest Restaurant is Closing in on 300 Years Old!", WPUR, April 11, 2023. Accessed July 7, 2023. "New Jersey's oldest continuously running restaurant has been in business since 1742.... The Black Horse Tavern and Pub is located in Mendham and is open for 7 days."

New Jersey Monthly magazine ranked Mendham Borough as the number one place to live in the state in its 2013 rankings of the "Best Places to Live" in New Jersey.Staab, Amanda. "Mendham: The Borough Tops Our List of NJ Towns It’s not unusual for folks in Mendham Borough to lend their neighbors a hand. But more than the Morris County town’s strong sense of community makes it number one in New Jersey Monthly’s 2013 Top Towns survey.", New Jersey Monthly, August 15, 2013. Accessed February 16, 2020.

In the Forbes magazine's 2006 (209th; median sale price of $835,000) and 2012 (356th; $800,672) rankings of the Most Expensive ZIP Codes in the United States, Mendham was listed among the top 500 nationwide."Most expensive ZIP codes 2006: New Jersey", Forbes, April 24, 2006. Accessed September 17, 2013.Brennan, Morgan. "Most Expensive ZIP Codes: 2012", Forbes, October 16, 2012. Accessed February 19, 2020. In 2018, New Jersey Business Magazine listed Mendham at 41st in its listing of "The Most Expensive ZIP Codes in New Jersey", with a median sale price 2017 of $650,000.

Along with Mendham Township, the Mendhams have been described by The New York Times as "both affluent".Gangsberg, Martin. "Two Mendhams—And Both Affluent", The New York Times, October 14, 1973. Accessed October 7, 2020. The borough is one of the state's highest-income communities. Based on data from the American Community Survey (ACS) for 2014–2018, Mendham Borough residents had a median household income of $158,542, almost double the statewide median of $79,363.Cervenka, Susanne. "Rich in New Jersey: Here are the 50 wealthiest towns in the state. Is yours one of them?", Asbury Park Press, July 1, 2019. Accessed October 7, 2020. "The USA TODAY NETWORK New Jersey took a look at U.S. Census data to find the 50th wealthiest towns in the state and ranked them by median household income.... 39. Mendham Borough - County: Morris County; Median household income: $145,284; Percent making more than $200,000: 33.1%"

History Mendham Borough was incorporated by an act of the New Jersey Legislature on May 15, 1906, from portions of Mendham Township, because residents of what became the borough wanted sidewalks and street lights constructed while those that lived in what remained the township (including the communities of Brookside and Ralston) felt it was cost prohibitive in their more rural areas.Staff. "New Jersey Town Wins Youth Fight; Center Rises in Mendham as Dogged Conservatism Falls-- Scouts, Ex-Mayor Turn Tide Model for Similar Projects Two Major Allies", The New York Times, June 9, 1951. Accessed June 9, 2012. "The argument paralleled a political split in 1906, when Mendham Borough broke from the surrounding Mendham Township. The borough wanted city conveniences such as street lights and sidewalks and the township, largely with a farming population, objected to paying for such improvements."Snyder, John P. The Story of New Jersey's Civil Boundaries: 1606-1968, Bureau of Geology and Topography; Trenton, New Jersey; 1969. p. 194. Accessed May 30, 2024.Historical Timeline of Morris County Boundaries, Morris County Library. Accessed December 24, 2016. "1906, May 15. Mendham Borough is established from Mendham Township."

The formation of Mendham Borough from Mendham Township in 1906 began a series of new municipalities that were created in the Somerset Hills region.

Located on the borough's southern slope of Bernardsville Mountain in the Somerset Hills lies Wendover, the former estate of investment banker Walter Phelps Bliss (1870-1924). One of the largest mansions in the Mendhams, Wendover is now home to the Roxiticus Golf Club.History, Roxoticus Country Club. Accessed October 7, 2020.

Phoenix House was purchased by Arthur Whitney of Mendham Township in 1919 and deeded to the borough in 1938 for use as its municipal building."Freeholders Award Historic Marker to Mendham Borough for Phoenix House Project", Morris County, New Jersey, October 3, 2017. Accessed August 30, 2022. "Mendham Township resident and former State Senator Arthur Whitney purchased the house from the Phoenix family in 1919 and turned over the house to the community in 1938. The house has served as the Borough Hall since that time."

Name The Mendhams may be named for Mendham, Suffolk, England,Hutchinson, Viola L. The Origin of New Jersey Place Names, New Jersey Public Library Commission, May 1945. Accessed September 5, 2015. Spelled as "Myndham".Gannett, Henry. The Origin of Certain Place Names in the United States, p. 205. United States Government Printing Office, 1905. Accessed September 5, 2015. Note error in the name of the county. or the name may derive from the Native American word mendom (meaning "raspberry") or for an Earl of Mendham.Kelley, Tina. "An Outpost of New England", The New York Times, February 2, 2014. Accessed January 25, 2025. "The origin of the town's name — preserved on the sign of the Black Horse as 'I'll Mend 'Em' — has been the subject of animated debate. Did it come from the Indian word 'mendom,' for raspberry or huckleberry? Was it chosen to honor the British Earl of Mendham?... While many residents drive to adjoining communities to headquarters of companies like Merck and Verizon, some take the Midtown Direct train to New York from Morristown, which is about 15 minutes away, depending on traffic."Beck, Henry Charlton. Tales and Towns of Northern New Jersey, pp. 128-149. Rutgers University Press, 1983. . Accessed September 5, 2015.

Historic district

The Mendham Historic District is a historic district located along stretches of Route 24, known in Mendham as Main Street. This east-west roadway is well over 200 years old, and has been called the Washington Turnpike, the Mendham-Morristown Road, and the William Penn Highway at various times in its history.National Register of Historic Places Inventory—Nomination Form for the Mendham Historic District, National Park Service. Accessed July 7, 2023. The district was added to the National Register of Historic Places on April 18, 1985, for its significance in agriculture, commerce, architecture, settlement, and religion from 1750 to 1924. The district includes 140 contributing buildings. With Since 1999, Mendham Borough has had a Historic Preservation Ordinance designed and intended to enhance and preserve the district's historic character.Master Plan: Historic Preservation Element, Mendham Borough. Accessed July 7, 2023.

According to the National Park Service:

The Mendham Historic District consists of 140 properties, generally well preserved, that illustrate the history of the village from its eighteenth century founding through its 1906 incorporation as a borough, and into the first third of this century when infill building completed development within the historic bounds of the village. The District covers the central crossroads of the village, and extends as far as the area nineteenth century maps illustrate as "Mendham, P.O.", the village core containing the post office. The conjunction of religious, residential, and commercial buildings that have established Mendham's village character are well preserved today.

Geography According to the United States Census Bureau, the borough had a total area of 5.98 square miles (15.49 km2), including 5.93 square miles (15.36 km2) of land and 0.05 square miles (0.13 km2) of water (0.84%).

Nestled on the northern end of the Somerset Hills, the borough is completely surrounded by the larger Mendham Township along with Bernardsville in Somerset County to the south.Areas touching Mendham, MapIt. Accessed February 27, 2020.Morris County Municipalities Map, Morris County, New Jersey Department of Planning and Preservation. Accessed February 27, 2020.New Jersey Municipal Boundaries, New Jersey Department of Transportation. Accessed November 15, 2019.

An unnamed pond in the borough is the source of the Passaic River.Passaic River Headwaters, Great Swamp Watershed Association. Accessed July 3, 2018. "The Passaic River Headwaters is formed by the union of three tributaries, originating in Mendham Township, Mendham Borough, and Bernardsville.... The northernmost stem of the headwaters flows from Mendham High School and then through a mix of residential properties and protected land. " The North Branch Raritan River also originates in the borough.

As of 2026, the borough is a member of Local Leaders for Responsible Planning in order to address the borough's Mount Laurel doctrine-based housing obligations.

Demographics

2010 census The 2010 United States census counted 4,981 people, 1,722 households, and 1,326 families in the borough. The population density was 837.1 per square mile (323.2/km2). There were 1,798 housing units at an average density of 302.2 per square mile (116.7/km2). The racial makeup was 95.70% (4,767) White, 1.02% (51) Black or African American, 0.04% (2) Native American, 2.05% (102) Asian, 0.08% (4) Pacific Islander, 0.18% (9) from other races, and 0.92% (46) from two or more races. Hispanic or Latino of any race were 2.71% (135) of the population.