The Old State House (originally the Second Town-House; also the Court House, Province House, or Old Provincial State House) is a historic building at 206 Washington Street in Boston, Massachusetts, United States. Completed in 1713, it is the city's oldest extant public building, hosting the judicial, legislative, and executive branches of the Massachusetts provincial and state governments during the 18th century. At , it was also the tallest building in Boston until 1745. The Old State House is located on Boston's Freedom Trail and is designated as a National Historic Landmark and Boston Landmark.

Two buildings previously occupied the site: the First Town-House, which burned down in 1711, followed by the Second Town-House, which was rebuilt after being gutted by fire in 1747. The state legislature, the Massachusetts General Court, moved to the New State House in 1798, after which the Old State House was used by the municipal government. It was used as Boston's city hall after Isaiah Rogers refurbished the structure in 1830. After a new city hall opened in 1841, the structure was used by commercial tenants for four decades. George A. Clough renovated the Old State House in 1881–1882, following threats of demolition, and the Bostonian Society took over much of the building. The Old State House has functioned as a history museum since then, undergoing additional renovations in the 20th and 21st centuries.

The building has a brick facade and rises stories above a partially raised basement. The facade is divided vertically into bays, with entrances on three sides and a balcony facing east. It has a gable roof with decorations such as a lion and unicorn, topped by a central tower. The interior has been modified repeatedly; the modern layout dates to Clough's renovation, with design details from various eras. The rooms are arranged around a spiral stair that passes through a rotunda. The basement has mechanical spaces and an entrance to the MBTA subway's State station, while the first and second stories have exhibit rooms flanking the rotunda. The building also has an attic and additional rooms in the tower. The museum hosts Boston-related exhibits and reenactments.

Site The Old State House is located at 206 Washington Street in Boston, Massachusetts, United States. It is bounded by Washington Street to the west; State Street to the north; and the intersection of State, Devonshire, and Congress streets to the east. A pedestrian street abuts the building to the south. The site slopes down to the east, where the basement has an entrance to the State station of the MBTA subway. Nearby buildings include One Boston Place to the west, the Ames Building and 28 State Street to the north, the Second Brazer Building to the southeast, and the Merchants Exchange building to the east (across Congress Street). The Old Corner Bookstore is also nearby to the south.

Just east of the building is a cobblestone memorial marker for the 1770 Boston Massacre, which took place nearby. Dating from , the marker formerly occupied a traffic island at State and Devonshire streets. The marker was moved in the early 2010s, when the State station was renovated. The modern marker is surrounded by a brass ring with stars. The Old State House and the Boston Massacre site are consecutive stops on the Freedom Trail, a path connecting historic sites in Boston.; Sequentially, they are between the Old South Meeting House and Faneuil Hall.

The site has been used by the public since 1634, when a public market was built there. Washington Street was the only link to Boston's Shawmut Peninsula before the peninsula was expanded via land reclamation. State Street, then known as King Street, ran east to Long Wharf. The wooden First Town-House, developed by Thomas Joy, was built on the Old State House's site in 1658 and burned in the fire of 1711.

History The modern Old State House, built on the site of the First Town-House, is Boston's oldest extant public building. Over the years, the Old State House has been known by multiple alternate names, including the Second Town-House, Province House, Court House, Old Provincial State House,Old provincial state house; maintenance and preservation – () or City Hall and variants thereof. Although the current structure's exterior dates from 1713, both the interior and exterior have been modified several times over the years.

Seat of colony government First building: 1712–1747 After the First Town-House burned down, the governments of the town of Boston, Suffolk County, and Massachusetts Bay Province lacked a meeting place. Town and provincial officials quickly agreed to erect a new building on the same site, and a committee was established in 1712 to construct a building of up to wide and long. The project was budgeted at 5,000 Massachusetts pounds. Based on the anticipated interior usage, the province paid half the cost, while the town and county paid one-fourth each. Samuel Sewall laid the cornerstone of the new building that May. William Payne built the Second Town-House; the designer is not known, but Robert Twelves is sometimes credited. Thomas Dawes has also been cited as the architect, but his contributions date from 1772.; The Massachusetts General Court, the provincial legislature, had moved into the building by April 1713, when its first session took place there.

The layout differed in several respects from the First Town-House. The basement was at least partially rented out, and the town government collected the rental income. The building's first floor housed a merchants' exchange, a feature derived from old English town halls; this space was enclosed, in contrast to the First Town-House's open-air market. The first floor also had records rooms for the county and province, and it had a post office at one point, along with two staircases ascending to the second floor. Stair lobbies separate that floor into three primary spaces, housing each of the province's three branches of government. From west to east, these were the Suffolk County and Massachusetts Supreme Judicial Court courtrooms; the General Court legislative chamber; and the Council Chamber of the Royal Governor. The central chamber was also used by the Boston Board of Selectmen, which governed the town. On the third floor were committee rooms for the selectmen. It is unknown how the attic was used.

There are no extant images of the full exterior as it originally appeared, though parts of the structure are shown in engravings of Boston overall. The original design likely appeared similar to the modern building, with oxeye windows, stepped gables, and a balcony. There was an octagonal tower with a bird-shaped weathervane. A 1743 view showed steps ascending to double doors on the eastern elevation of the facade, and there was also a sundial. Lion and unicorn motifs, representing the British, were installed between 1743 and 1751. At , the Second Town-House was the tallest building in Boston until 1745, when it was surpassed by the Old North Church in the North End.

The Second Town-House was used for government business, announcements, and ceremonies, including welcoming parties for new provincial governors. Politicians hosted commemorations and parties in the council room; announcements were made from the balcony; and (in at least one case) forgers were publicly humiliated on the steps below. The town's selectmen moved their meetings to the new Faneuil Hall in 1742. Colonists sometimes convened to protest provincial government actions, requiring frequent window repairs. A riot took place there in November 1747 after British leaders tried to "impress" colonists into serving in the British military.

1747 fire and reconstruction The Second Town-House was gutted by fire on December 9, 1747, after sparks from a first-floor hearth spread rapidly. The blaze destroyed all goods and records inside; the exterior brick walls survived the fire, and the window openings were quickly boarded up. Provincial meetings were temporarily relocated to Faneuil Hall. The provincial government considered relocating to another Massachusetts town or to present-day Maine, but had decided by March 1748 to rebuild on the same site. The modifications were budgeted at about 3,705 Massachusetts pounds, of which the province was to pay half, and the county and town would pay the rest. The town government, having moved most business to Faneuil Hall, unsuccessfully asked the General Court to waive the town's share of the costs. The modifications were completed within a year of the fire. The first exterior views specifically focusing on the building date from shortly afterward, in 1751.

The interior was rebuilt likely according to the original plan, although specific drawings of the layout have not emerged. Details of the first-floor space are scarce, but the Ancient and Honorable Artillery Company of Massachusetts sometimes used it for drills. Though Captain Francis Goelet wrote in 1750 that the first floor was open to the elements, later historians wrote that he may have been talking about Faneuil Hall. Two staircases ascended to lobbies between three second-floor rooms—from west to east, the Court, Representatives' and Council chambers. The third floor housed committee rooms and offices, while the basement was rented out. The exterior was altered: The gambrel roof was replaced by a gable roof, the octagonal tower was replaced by a tiered square tower, and the parapet on the eastern end was adorned with lion and unicorn figures. Beneath the eastern parapet, new laws were announced from a small balcony. For nearly a century afterward, significant modifications were mostly confined to the interior; the roof design persisted until 1870.

Rebuilt structure: 1750–1776

For the most part, the 1750s at the Town House were uneventful. During this time, the building featured portraits of British royals and notable Bostonians, along with maps. The Cape Ann earthquake of 1755 did not damage the building, but a later study found that it was structurally vulnerable to north–south transverse forces. The third-floor space had been subdivided no later than 1756, when its western end was designated as the General Court's committee room. When Faneuil Hall burned down in 1761, the town government temporarily returned to the Town House. Judicial activities were moved to a new courthouse in 1767 or 1769.

By the mid-1760s, there was growing pro-independence sentiment. This created friction between the legislative and executive branches, both of which met on the second floor. A visitor gallery was added on the western side of the Representatives' Chamber in 1766 or 1767. The gallery was built by Thomas Crafts at the behest of Massachusetts House of Representatives clerk Samuel Adams. This may have been the first public gallery in a legislative room in the United States.

In response to protests over taxes, the British government sent troops to Boston in September 1768 and pointed weaponry at the Town House's front door, prompting the General Court to move to Faneuil Hall. The legislature, refusing to convene at the Town House while British troops were present, temporarily moved to Cambridge in 1769. The British used the building as a military barracks during that time, moving into the first floor. The balcony was likely fixed by mid-1770. Once the troops had left in late 1772, the General Court moved back to the building. Renovations took place the next year. These modifications involved the "taking down the East End and rebuilding", along with repainting the exterior. The first use of the name "State House" dates from this time.

Notable colonial-era events