The Boston Post Road was a system of mail-delivery routes between New York City and Boston, Massachusetts, that evolved into one of the first major highways in the United States.

The three major alignments were the Lower Post Road (now U.S. Route 1 (US 1) along the shore via Providence, Rhode Island), the Upper Post Road (now US 5 and US 20 from New Haven, Connecticut, by way of Springfield, Massachusetts), and the Middle Post Road (which diverged from the Upper Road in Hartford, Connecticut, and ran northeastward to Boston via Pomfret, Connecticut).

In some towns, the area near the Boston Post Road has been placed on the National Register of Historic Places, since it was often the first road in the area, and some buildings of historical significance were built along it. The Boston Post Road Historic District, including part of the road in Rye, New York, has been designated a National Historic Landmark. The Post Road is also famous for milestones that date from the 18th century, many of which survive to this day. In parts of Connecticut (generally east of Hartford), it is also known as Route 6.

History The Upper Post Road was originally called the Pequot Path and had been in use by Native Americans long before Europeans arrived.Bourne, p.13 Some of these important native trails were in many places as narrow as two feet.

What is now called the Old Connecticut Path and the Bay Path were used by John Winthrop the Younger to travel from Boston to Springfield in November 1645, and these form much of the basis for the Upper Post Road.

The colonists first used this trail to deliver the mail using post riders. The first ride to lay out the Upper Post Road started on January 1, 1673.Daughters of the American Revolution Magazine, January 1917, Vol. 50, page 386, Later, the newly blazed trail was widened and smoothed to the point where horse-drawn wagons or stagecoaches could use the road. The country's first successful long-distance stagecoach service was launched by Levi Pease along the upper road in October 1783."How the Post Road wrote New England’s history", The Boston Globe

During the 19th century, turnpike companies took over and improved pieces of the road. Large sections of the various routes are still called the King's Highway and Boston Post Road. Much of the Post Road is now U.S. Route 1, U.S. Route 5, and U.S. Route 20.

Mileposts were measured from the intersection of Broadway and Wall Street in New York (one block west of Federal Hall) and from the old Boston city-line on Washington Street, near the present-day Massachusetts Turnpike.

The Metropolitan Railroad Company was chartered in 1853 to run streetcars down the stretch of the road on Washington Street in Roxbury, which is now served by the MBTA Silver Line. The Upper and Lower Boston Post Roads were designated U.S. Routes 1 and 20 in 1925 (though Route 20 has since been substantially modified).

New York

Manhattan Much of the route in Manhattan, where it was known as the Eastern Post Road, was abandoned between 1839 and 1844, when the current street grid was laid out as part of the Commissioners' Plan that had been originally advanced in 1811. The following sections of the road still exist: Broadway – Park Row – Bowery – Fourth Avenue – Broadway from Wall Street (the southern end of the Post Road) to Madison Square Park There is a large gap in midtown Manhattan before Post Road resumes its course north of Central Park St. Nicholas Avenue-Broadway: St. Nicholas Avenue from 110th Street (with a realignment near 145th Street), switching to Broadway at 169th Street and continuing to 228th Street 228th Street-Kingsbridge Avenue from Broadway to the old Kings Bridge over the old Harlem River bed. (The course of the Harlem River was altered in 1895.)

These milestones were once present in Manhattan: 1 – the west side of Bowery near Rivington StreetOne Mile House, on the corner of Rivington Street, demolished in 1921, was a meeting-ground for Tammany Hall politicians. "Bowery Landmark in $170,000 lease", The New York Times 1 April 1921; the painted sign for One Mile House, on the flank of a building on the east side of Bowery, survived into the 1980s. 2 – southwest corner of Astor Place and Fourth Avenue 3 – Madison Avenue and 26th Street 4 – east side of Third Avenue, halfway between 45th Street and 46th Street 5 – west side of Second Avenue at 62nd Street 6 – northwest corner of Third Avenue and 81st Street 7 – in Central Park, west of Fifth Avenue, between 97th Street and 98th Street 8 – St. Nicholas Avenue, west side, between 115th Street and 116th Street 9 – St. Nicholas Avenue, west side, opposite north line of 133rd Street 10 – southwest corner of St. Nicholas Avenue and 152nd Street 11 – Broadway, west side, near 170th Street or 171st Street ~ Now at Roger Morris Park next to the Morris-Jumel Manse 40°50'04.7"N 73°56'18.5"W 12 – Broadway, west side, at or near 189th Street ~ Now at the Broadway entrance to Isham Park 40°52'06.4"N+73°55'08.9"W 13 – east side of Broadway between Academy Street and 204th Street 14 – Broadway, west side, between 225th Street and 228th Street

The Bronx

In southwestern Westchester County, now the Bronx, the Boston Post Road came off the Kings Bridge and quickly turned east, with the Albany Post Road continuing north to Albany, New York. It passed over the Bronx River on the Williams Bridge, and left The Bronx on Bussing Avenue, becoming Kingsbridge Road in Westchester County. In more detail, it used the following modern roads:

Kingsbridge Avenue – 230th Street – Broadway – 231st Street Albany Post Road continued north on Albany Crescent Albany Crescent – Kingsbridge Terrace – Heath Avenue gap across Jerome Park Reservoir Van Cortlandt Avenue gap at Williamsbridge Reservoir Reservoir Place – Gun Hill Road – White Plains Road (southbound lanes) gap from near 217th Street to near 231st Street Bussing Avenue gap from Grace Avenue to De Reimer Avenue Bussing Place – Bussing Avenue

Westchester County Pelham Manor New Rochelle Larchmont Mamaroneck Rye Port Chester

The Boston Post Road entered what is now Westchester County on Kingsbridge Road, and turned north on Third Avenue-Columbus Avenue (Route 22), forking off onto Colonial Place. It continued across Sandford Boulevard (Sixth Street) where there is no longer a road, and curved east and southeast around the hill, hitting Sandford Boulevard-Colonial Avenue at the Hutchinson River Parkway interchange. It then continued east on Colonial Avenue-Kings Highway, merging with U.S. Route 1. From there to the Connecticut border, the Post Road used US 1, except for several places, where Post Road used the following roads: The southbound side of US 1-Huguenot Street through downtown New Rochelle. Old Boston Post Road north of downtown New Rochelle. Old Post Road-Orienta Avenue south of downtown Mamaroneck. Mamaroneck Avenue-Prospect Avenue-Tompkins Avenue north of downtown Mamaroneck. Old Post Road at Playland Parkway in Rye.

Upper Post Road The Upper Post Road was the most traveled of the three routes, being the furthest from the shore and thus having the fewest and shortest river crossings. It was also considered to have the best taverns, which contributed to its popularity. The Upper Post Road roughly corresponds to the alignment of U.S. Route 5 from New Haven, Connecticut, to Hartford; Connecticut Route 159 from Hartford to Springfield, Massachusetts; U.S. Route 20 from Springfield to Warren, Massachusetts (via Route 67); Massachusetts Route 9 from Warren to Worcester; an unnumbered road (Lincoln Street in Worcester, Main Street in Shrewsbury, and West Main Street in Northborough) to Northborough; and U.S. Route 20 from Northborough to Boston. A series of historic milestones erected in the 18th century survive along its route from Springfield to Boston.

Connecticut

Massachusetts

Lower Post Road The Lower Post Road hugged the shoreline of Long Island Sound all the way to Rhode Island and then turned north through Providence to Boston. It traversed what is now the most densely populated part of Connecticut, including the state's three largest cities; as a result, it is the best-known of the routes today. The Lower Post Road roughly corresponds to the original alignment of U.S. Route 1 in eastern Connecticut, Rhode Island, and Massachusetts.

Connecticut

Greenwich Stamford Norwalk Darien The road is Darien's main thoroughfare. Most businesses as well as both Metro-North stations, Darien and Noroton Heights. Westport Fairfield Bridgeport The road marked the northern end for Bridgeport's historical population during the 1800s. A plaque placed in 1915 at the intersection of East Main Street and US 1 (Post Road) makes reference to the first United States Postal Service Road, first used in 1678. The plaque is mounted on a 2-foot tall stone. There is also another down the road east in Stratford.

Stratford A plaque placed in 1915 at the intersection of Edgewood Street and US 1 (Post Road) makes reference to the first United States Postal Service Road, first used in 1678. The plaque is mounted on a 2-foot tall stone approximately 50 feet east of Edgewood Street in front of 1757 Barnum Avenue. Milford Orange West Haven New Haven Old Saybrook Old Lyme, this stretch of the road is a national historic district New London

Rhode Island

Massachusetts In Massachusetts, the Norfolk and Bristol Turnpike was established in 1803 as a straighter route between Pawtucket, Rhode Island, and Roxbury, Massachusetts, mostly west of the Post Road. It is known as Washington Street in many of the towns it passes through. Due to its avoidance of built-up areas, the southern half of this road was little-used. In addition, another well-used route passed west of this turnpike along current Route 1A.

South Attleboro The Post Road entered Massachusetts at the town of Attleboro's Newport Avenue (Route 1A) through the settlement of South Attleboro. It continued northeast on Newport Avenue along Route 123, splitting to the north (staying with Newport Avenue) to cross into North Attleborough.

North Attleborough South of North Attleborough center, the old road is known as Old Post Road. The old road crossed the turnpike (now US 1) just south of the intersection with Route 120, forming a small curve before merging with the turnpike north of the intersection. This curved alignment is now gone, so traffic must use US 1. Additionally, US 1 leaves the turnpike at the Route 120 intersection to bypass North Attleborough center on East Washington Street.

The Lower Post Road passed through North Attleborough Center on Washington Street, later used as part of the turnpike. Another short curved alignment still exists to the west of Washington Street north of the center, now called "Park Street". Just north of this, the route crosses the Ten Mile River and then enters a complicated five-way intersection with US 1 and Route 1A. US 1 straight ahead is the old turnpike, and US 1 to the right was built in the 1930s. The Post Road went to the right onto Elmwood Street. The fork to the left onto Route 1A through Plainville center was an alternate route to Boston.

Elmwood Street enters the town of Plainville, where it becomes Messenger Street. The road merges with Route 106 before crossing Route 152 at Wilkins Four Corners and entering Foxborough.

Sharon There is a road passing from the town of Sharon into East Walpole which is known as Old Post Road, which continues north as Pleasant Street into Norwood.

East Walpole (part of Walpole)

Norwood In Norwood, the oldest route of the Post Road followed Neponset Street south until the intersection with Pleasant Street. The newer route followed Washington Street through the center of Norwood, south towards Walpole.

Islington (part of Westwood) The Post Road turned from East Street onto Washington Street, heading south towards Norwood.

Dedham