The Mount's main house was inspired by the 17th-century Belton House in England, with additional influences from classical Italian and French architecture. Edith Wharton used the principles described in her first book, "The Decoration of Houses" (co-authored with Ogden Codman, Jr.), when she designed the house. She thought that good architectural expression included order, scale, and harmony. Its west (entry) elevation is three stories; on the garden side it is two stories with an opening out to a large, raised, stone terrace overlooking the grounds. The house exterior is a striking white stucco, strongly set off by dark green shutters, and rises from a quasi-rustic foundation of coarse field stone. Clusters of gables and white chimneys rise from the roof, which is capped with a balustrade and cupola. This main house is augmented by Georgian Revival gatehouse and stable, and a beautifully restored Lord and Burnham Greenhouse. Wharton's sometime collaborator, Ogden Codman, Jr., assisted with the architectural design. Wharton's niece, Beatrix Jones Farrand, designed the kitchen garden and the drive; Farrand was the only woman of the eleven founders of the American Society of Landscape Architects.