1/4 Scale Detail of Stair at End of Wing, Old Faithful Inn, Yellowstone National Park, 1927

1/4 Scale Plan of Porch and Main Stairs, Old Faithful Inn, Yellowstone National Park, 1927

12 Inch Butterfly Valve with 9 Inch Relief Outlet, D'Olier Engineering Company

12 Inch Butterfly Valve with 9 Inch Relief Outlet, D'Olier Engineering Company

12 Inch Butterfly Valve, D'Olier Engineering Company

1st Floor Plan, Lake Hotel, Yellowstone Park, Plan of Bed Rooms, 1919

2nd Floor, Lake Hotel, Yellowstone Park, Plan of Bed Rooms, 1919

3rd Floor, Lake Hotel, Yellowstone Park, Plan of Bed Rooms, 1919

A Boat House at the Lake, Yellowstone National Park, 1926

Addition to Canyon Cafeteria & Housekeepers Headquarters, Yellowstone Park Camp Company, 1935

Addition to Central Building, Canyon Camp, Yellowstone Park Camps Company, 1935

Addition to Dining Room, Old Faithful Inn, Yellowstone National Park, 1927

Addition to Girls Dormitory, Canyon Hotel, Yellowstone Park Hotel Company, Wyoming, 1929

Addition to Girls Dormitory, Canyon Hotel, Yellowstone Park Hotel Company, Yellowstone Park, Wyoming, 1929

Addition to Kitchen, Old Faithful Inn, Yellowstone Park Hotel Company, 1929

Addition to Mammoth Hotel, Yellowstone Park, Wyoming

Addition to Mammoth Hotel, Yellowstone Park, Wyoming

Addition to Old Faithful Inn, Sheet 2 [of 8], Yellowstone National Park, 1927

Addition to Old Faithful Inn, Sheet 3 [of 8], Yellowstone National Park, 1927

Addition to Old Faithful Inn, Sheet 4 [of 8], Yellowstone National Park, 1927

Addition to Old Faithful Inn, Sheet 5 [of 8], Yellowstone National Park, 1927

Addition to Old Faithful Inn, Sheet 7 [of 8], Yellowstone National Park, 1927

Addition to Old Faithful Inn, Sheet 8 [of 8], Yellowstone National Park, 1927

Army Era: Buildings, Services, & Utilities

Army Era: Concessioners & Partners

Army Era: Land Survey & Boundary Maps

Army Era: Roads

Civilian Superintendents Era

Facilities & Maintenance: Buildings

Facilities & Maintenance: Roads & Trails

Master & Area Plans

Resource Management: Wildlife

Yellowstone National Park Heritage and Research Center