The cloistering of Harvard Yard culminated in the early 1920s with the recommendations of a committee led by architects Charles A. Coolidge and Guy Lowell. They proposed constructing a number of buildings that would be erected at the edges of the Yard, further buffering it from the city. Lehman Hall, originally the Bursar's Office, was sited at the southwest corner, providing a focus for a walkway on a diagonal axis that leads from the Yard into Harvard Square (HS1). Designed by Coolidge, Shepley, Bulfinch and Abbott, it was built in 1924–1925, along with two freshman dormitories, Mower and Lionel halls. In 1926 the firm designed Straus Hall, and Wigglesworth followed in 1930. These red brick Georgian Revival buildings accompanied a larger construction effort undertaken by President A. Lawrence Lowell, whose tenure between 1909 and 1933 was a watershed period for the modern campus. Beyond the Yard, Lowell and Coolidge developed their vision for the “houses,” or dormitories, built along the Charles River for the upperclassmen.