Boston

Boston is a city in the United States.

It sits beside the sea. Boats float in its harbor, and tall buildings stand near the water.

Boston is the capital of Massachusetts, a state in the northeast of the United States. The city sits on a harbor that opens onto the Atlantic Ocean, and boats and ferries have crossed its waters for nearly 400 years.

The 2020 census counted 675,647 people in the city of Boston. The U.S. Census Bureau's newest estimate, for 1 July 2025, is 672,973. Many more people live in the towns and cities around it.

Boston is the capital of the Commonwealth of Massachusetts and the seat of Suffolk County. It grew on a hilly peninsula in a sheltered harbor, a site that National Geographic notes had a dependable supply of spring water and was well placed for trade by sea.

The 2020 census counted 675,647 residents. The Census Bureau's Vintage 2025 estimates put the city at 672,973 on 1 July 2025, after a low of 659,884 in 2021. The Massachusetts Bay Transportation Authority, which runs the region's subway, buses, ferries and commuter rail, serves nearly 200 cities and towns around Boston.

In Boston you can follow a long trail on foot. It takes you to old meeting halls, old churches and an old ship.

A tall stone tower stands on a hill. It remembers a battle from long ago.

The Freedom Trail is a walking path 2.5 miles (about 4 kilometers) long. It winds through downtown Boston and Charlestown and links 16 official historic sites, among them Faneuil Hall, the Paul Revere House and the Old North Church.

In Charlestown, the Bunker Hill Monument is a granite obelisk 221 feet (about 67 meters) tall, dedicated in 1843. Nearby, at the Charlestown Navy Yard, floats USS Constitution, a wooden warship launched in Boston in 1797. The National Park Service calls it the oldest commissioned warship afloat in the world.

Boston National Historical Park is a partnership of federally, municipally and privately owned sites tied to the colonial struggle for independence. The Freedom Trail, a 2.5-mile route through downtown and Charlestown, connects 16 official historic sites, including Faneuil Hall, the historic town meeting space, the Paul Revere House and the Old North Church.

The Marquis de Lafayette laid the cornerstone of the Bunker Hill Monument 50 years after the battle; the 221-foot granite obelisk took more than 17 years to finish and was dedicated in 1843 on Breed's Hill. USS Constitution, built at Hartt's shipyard in the North End and launched on 21 October 1797, earned the nickname "Old Ironsides" in the War of 1812. The Park Service describes it as the oldest commissioned warship afloat in the world; Navy sailors still serve aboard.

Boston was once a small piece of land with lots of water around it.

People moved dirt from the hills into the water. Bit by bit, they made new land to build on.

Soon after 1630, Bostonians began to make their peninsula bigger. They dug soil from the town's hills and dumped it into ponds, coves and muddy tidal flats. Beacon Hill is about 60 feet (18 meters) lower today than it was before the digging began.

The biggest project was the Back Bay, a wide area of tidal flats. Filling began in earnest in 1850, with trash, mud and sand and gravel brought in by train, and it was not finished until the 1890s. Today Boston has more than 5,000 acres of man-made land.

Land-making began early. In the 1640s a dam across a cove at the north end of the peninsula created Mill Pond to power tide mills; from 1807 the pond was filled, largely with earth from Beacon Hill, which now stands about 60 feet lower than it once did, creating some 50 acres known today as the Bulfinch Triangle.

A mill dam built in 1822 cut off the Back Bay, and railroad lines across it in the 1830s worsened the water's circulation. Large-scale filling began in 1850 using trash, mud from the South Bay, and sand and gravel hauled by rail from Needham, and was completed in the 1890s. Buildings on this fill rest on wooden pilings 30 to 40 feet long that must stay below the water table to avoid rot; since 1986 the Boston Groundwater Trust has tracked water levels through a network of monitoring wells.

In Boston, people can ride a ferry boat across the water.

Trains also run under the ground. Boston's first underground train tunnel opened a long, long time ago.

People have taken ferries in Boston since 1631, when Thomas Williams began a ferry between Boston and Charlestown. Horse-drawn cars on rails came in 1856, and the first electric streetcar ran on 1 January 1889.

Tremont Street became so crowded with streetcars that a tunnel was built for them under the street. It opened in 1897, and the MBTA calls it North America's first subway tunnel. It is still used today. Boston's transit system, the MBTA, is known as "the T," and its lines have colors: the Red Line was named for the crimson color of Harvard University, where it ended.

The MBTA traces public transport in Boston to 1631, when Thomas Williams opened a chartered ferry between the Shawmut peninsula and Charlestown. A stagecoach to Cambridge followed in 1793, horsecars on rails in 1856, and the first electric streetcar on 1 January 1889.

To relieve congestion on Tremont Street, a commission recommended a tunnel for streetcars; opened in 1897 and described by the MBTA as North America's first subway tunnel, it still links Government Center, Park Street and Boylston stations. The MBTA was voted into law on 3 August 1964 as a state agency serving 78 municipalities. The color-coded map was made after the 1965 consolidation: crimson red for the line ending at Harvard, blue for the line running under Boston Harbor.

Boston has a very old park called the Common. Long ago, cows ate grass there. Now children skate on its pond in winter.

Boston also has a big free library and a famous running race.

Boston Common was founded in 1634, and the City of Boston calls it America's oldest park. It began as shared land where animals grazed and soldiers trained. Later, cows were banned and people planted trees and added fountains. Today children skate on the Frog Pond in winter and splash in its spray pool in summer.

The Boston Public Library, set up in 1848, says it was the first large free city library in the United States. The Boston Marathon was first run on 19 April 1897, with just 15 runners at the start.

Boston Common, founded in 1634, was first a working common ground for grazing and militia drills; its peaks were later leveled, cows were banned, and 19th-century Bostonians added trees, fountains and statues. The City calls it America's oldest park.

The Boston Public Library, established in 1848, describes itself as the first large free municipal library in the United States, the first public library to lend books and the first with a children's room. Its McKim building in Copley Square opened in 1895, and the library holds more than 23 million items. The Boston Athletic Association's first marathon, a 24.5-mile road race from Ashland, was run on 19 April 1897 with 15 starters and 10 finishers; the course was later lengthened to 26.2 miles and moved its start to Hopkinton.