The Blithewold Mansion, Gardens and Arboretum is an arboretum of 13 hectares (32 acres), located at 101 Ferry Road, Bristol, Rhode Island, midway between Newport and Providence, Rhode Island, on Bristol Harbor with views over Narragansett Bay.

The mansion was built in Queen Anne style in 1895, then rebuilt in 1906 as Blithewold II after being destroyed by fire.

Since 1978 the house has been open as a public museum, restored to its appearance circa 1910, with an extensive collection of the Van Wickle's personal possessions, including furniture, decorative arts, letters and other writings, Marjorie's original watercolors, and an extensive collection and display of women's dresses and other costumes of the period.

The grounds also include English Yews (Taxus baccata) and Eastern Junipers (Juniperus virginiana), as well as what is claimed to be the largest Giant Sequoia (Sequoiadendron giganteum) on the East Coast, and currently about 100 feet (30 m) tall.

[5] Blithewold is home to at least two Rhode Island Champion Trees, including a Sargent’s Weeping Hemlock (Tsuga canadensis ‘Sargentii’, planted ca.