The Breakers is the grandest of Newport's summer "cottages" and a symbol of the Vanderbilt family's social and financial preeminence in turn-of-the-century America. Commodore Cornelius Vanderbilt (1794–1877) established the family fortune in steamships and later in the New York Central Railroad, which was a pivotal development in the industrial growth of the nation during the late 19th century. The Commodore's grandson, Cornelius Vanderbilt II, became Chairman and President of the New York Central Railroad system in 1885, and purchased a wooden house called The Breakers in Newport during that same year. In 1893, he commissioned architect Richard Morris Hunt to design a villa to replace the earlier wood-framed house which was destroyed by fire the previous year. Hunt directed an international team of craftsmen and artisans to create a 70-room Italian Renaissance- style palazzo inspired by the 16th-century palaces of Genoa and Turin. Allard and Sons of Paris assisted Hunt with furnishings and fixtures, Austro-American sculptor Karl Bitter designed relief sculpture, and Boston architect Ogden Codman decorated the family quarters.

The mansion offers tours.

Marble House was built between 1888 and 1892 for Mr. and Mrs. William K. Vanderbilt, a summer house, or "cottage," as Newporters called them in remembrance of the modest houses of the early 19th century. But Marble House was much more; it was a social and architectural landmark that set the pace for Newport's subsequent transformation from a quiet summer colony of wooden houses to the legendary resort of opulent stone palaces.

The house offers tours.

The Merchant's House Museum is New York City's only family home preserved intact, both the interior and exterior, from the 19th century. Built in 1832, this red-brick and white-marble late Federal and Greek Revival row house on East Fourth Street was home to a prosperous merchant family for almost 100 years (1835–1933). The façade, with its steeply pitched roof, dormer windows, marble door surround, and elaborate fan light recalls earlier Federal-style homes; while, inside, the formal Greek Revival parlors reflect the latest architectural fashion of the day. The Merchant's House is considered New York City's prime example of a Greek Revival home. Complete with the family's original furnishings and personal possessions, the house offers a rare and intimate glimpse of domestic life during the pivotal era of the 19th century when New York City was transformed from a colonial seaport into a thriving metropolis and the center of U.S. commerce. Three floors and eight period rooms display the possessions of the inhabitants—including their furnishings, clothing, and personal items. The costume collection includes 420 articles of clothing—primarily women’s dresses and their accompanying accessories, such as petticoats, collars, undersleeves, and chemisettes. The majority of the dresses range from 1840–1885, with two examples of 1830s dresses and an extremely rare dress ca. 1813-1815 that is in excellent condition, as well as a rare mid–19th–century corset. The 19th–century rear garden is also open for viewing.

The museum offers self-guided tours, mp3 download or cell phone audio tours, guided house tours on a variety of subjects, guided neighborhood tours, an introductory slide show, docents available to answer questions, an outreach slide show and lecture program, a traditional afternoon tea, period rooms, online exhibits, and the option of friending Gertrude Tredwell (one of the houses residents, 1840–1933) on My Space or Facebook.

The Society maintains the Barn Visitors Center, as well as three 18th-century historic sites: the 1725 John Chads House, the John Chads Springhouse, and the 1720s Barns-Brinton House.

The society offers educational programs, lectures, research library access, and occasional recreational and educational events; the Center offers exhibits; the John Chads House offers tours; the Barns-Brinton House offers tours.

The Elms was the summer residence of Mr. and Mrs. Edward Julius Berwind of Philadelphia and New York. Mr. Berwind made his fortune in the Pennsylvania coal industry. In 1898, the Berwinds engaged Philadelphia architect Horace Trumbauer to design a house modeled after the mid-18th-century French chateau d'Asnieres (circa 1750) outside Paris. Construction of The Elms was completed in 1901 at a cost reported at approximately $1.4 million. The interiors and furnishings were designed by Allard and Sons of Paris and were the setting for the Berwinds' collection of Renaissance ceramics, 18th-century French and Venetian paintings, and Oriental jades. The elaborate Classical Revival gardens on the grounds were developed between 1907 and 1914. They include terraces displaying marble and bronze sculpture; a park of fine specimen trees; and a lavish lower garden featuring marble pavilions, fountains, a sunken garden, and carriage house and garage.

The mansion offers tours.