Mansion House (also referred to as Ellarslie and McCall House) is a historic residence located in Trenton, Mercer County, New Jersey, United States. The house was built as a summer residence for Henry McCall Sr. of Philadelphia in 1848, and is one of the earliest examples of Italianate architecture in the United States. Since 1978 the building has been home to the Trenton City Museum, which features collections of decorative and fine arts.