Othniel C. Marsh House

Marsh Hall, formally known as Othniel C. Marsh House, is a historic house at 360 Prospect Street on Prospect Hill in New Haven, Connecticut. The property, which includes the house and a 6.8 acres (2.8 ha) area, was declared a National Historic Landmark in 1965.

The four-story brownstone house was built in 1878, It was designed by J. Cleaveland Cady as the residence of Yale professor and paleontologist Othniel Marsh. Marsh left his estate to the university in 1899. The house and surrounding gardens were the first facilities of the Yale School of Forestry.

The grounds are known as Marsh Botanical Garden.

Marsh Hall currently houses offices of the Yale School of Forestry and Environmental Studies, including the "Global Institute of Sustainable Forestry".