Renowned French Impressionist paintings—four by Claude Monet, three by Edgar Dega—and notable works by Édouard Manet, Mary Cassatt, and James McNeill Whistler are highlights of the Museum's in situ exhibition. The 152-acre property features an Arts and Crafts carriage barn and theater, stone garages, woodland trails, a pond and dairy complex, and a Sunken Garden designed by Beatrix Farrand c. 1920.

The museum offers exhibits, tours, research library access, educational programs, and recreational and educational events.

The Museum provides professional scholarship, preservation, and historical programming about Mattatuck heritage, stimulates interest in the fine and decorative arts of Connecticut by showcasing their highest quality and expression, and encourages an appreciation of the humanities and the fine arts through its collections, exhibits, and programs. It houses permanent local history and art exhibits.

The museum offers exhibits, tours, reference library access, educational programs, and recreational and educational events.

The Harriet Beecher Stowe Center preserves and interprets Stowe's Hartford home and the Center's historic collections, promotes vibrant discussion of her life and work, and inspires commitment to social justice and positive change. A visit to the Center includes the Harriet Beecher Stowe House, a Victorian Gothic Revival home (1871) which includes Victorian-style gardens; the Katharine Seymour Day House (1884), a mansion adjacent to the Stowe House; and the Stowe Visitor Center (1873), with changing exhibitions.

The center offers exhibits, tours, reference library access, and occasional recreational and educational events.

Located on the historic Cos Cob Harbor, home of Connecticut's first art colony, the Society's facilities include the National Historic Landmark Bush-Holley House (c. 1730); the Visitor Center, housed in a former village post office (c. 1805); the Hugh and Claire Vanderbilt Education Center, set in a mid-19th century barn and artists' studio; and the William E. Finch, Jr. Archives.

Bush-Holley House is the centerpiece of Bush-Holley Historic Site on Cos Cob Harbor. A unique dual interpretation provides visitors with two distinct museum experiences that portray the history of the house: the era of the Bushes, a colonial family who lived and farmed on the site from 1790 to 1825, and the Cos Cob art colony period from 1890 to 1920. Eight rooms tell a story of change over time, beginning with the turn of the 20th century and moving backward in time to the Federal era. On the outside the historic buildings, landscape and gardens are restored to c. 1900.

The society offers exhibits, educational programs, research library access, and recreational and educational events; the Bush-Holley Historic Site offers tours and occasional recreational and educational events.

The museum of the Westerly Armory displays both community and military memorabilia in order to preserve community, state, and national history. The Armory itself is an artifact, built in 1901–02 and designed by the firm of William R. Walker and Son. It was the second Walker armory, following Pawtucket.

The museum offers tours, exhibits, and occasional recreational and educational events.

The Redwood Library and Athenæum is the oldest lending library in America, and the oldest library building in continuous use in the country. Founded in 1747 by 46 proprietors upon the principle of "having nothing in view but the good of mankind," its mission continues over 250 years later.

The library offers tours, exhibits, and all standard library services (including recreational and educational events, though not focused specifically on history).

The Society's Museum, housed in the 1865 Christian Union Church, displays exhibits related to local history. The Society also operates the 1725 Southermost Schoolhouse and the 19th-century Old Town Hall.

The museum offers exhibits and research library access; the Old Town Hall offers exhibits.

The Maxwell House was built between 1752 and 1756 by the Reverend Samuel Maxwell. The house, which is the oldest brick dwelling in Warren, is distinguished by the distinctive Flemish bond pattern of the brickwork, its field stone foundation, and its large central chimney. The Maxwell House is maintained by the Society as a working museum.

The house offers tours, educational programs, and occasional recreational and educational events.

The Birthplace serves as a showplace for reproductions of the works of one of America's foremost portrait painters and as an authentically restored and furnished workingman's home and the site of the first snuff mill in America. The wooded homestead on the banks of the Mattatuxet Brook also features a partially restored grist mill and a fish ladder. In spring the ladder is packed with migrating herring, swimming furiously to reach the pond above the mill dam. The grist mill houses the original fine-grained granite stones used to grind corn for the famous Rhode Island Johnny Cakes.

The site offers tours and occasional recreational and educational events.

Built by Eleazor Arnold in 1693, the Arnold House is a rare surviving example of a "stone-ender," a once common building type first developed in the western part of England.

The house offers tours and educational programs.