Lynnewood Hall is a 110-room Neoclassical Revival mansion in Elkins Park, Pennsylvania. It was designed by the architect Horace Trumbauer for the industrialist Peter A. B. Widener and built between 1897 and 1899. Lynnewood Hall is the second largest surviving Gilded Age mansion in the United States. It once housed one of the most significant art collections in U.S. history, amassed by Peter and his son Joseph E. Widener. The collection was subsequently donated to the National Gallery of Art in 1942. Lynnewood Hall was abandoned in the late 1990s. In 2023, it was purchased by the Lynnewood Hall Preservation Foundation, which has begun restoration of the house and grounds. These images were photographed in August 2026, prior to restoration. The property was listed on the National Register of Historic Places in 2025