To encourage domestic tourism and to promote America's national parks, a series of ten stamps was issued on various dates from July 16 to October 8, 1934. In denominations of 1- to 10-cents, the stamps depict scenes from the national parks in various colors.
- 1-cent green, El Capitan, Yosemite National Park, California
- 2-cent red, Grand Canyon National Park, Arizona
- 3-cent violet, Mirror Lake, Mount Rainier National Park, Washington
- 4-cent brown, Mesa Verde National Park, Colorado
- 5-cent blue, Old Faithful Geyser, Yellowstone National Park, Wyoming
- 6-cent dark blue, Crater Lake National Park, Oregon
- 7-cent black, Great Head, Acadia National Park, Maine
- 8-cent sage green, Great White Throne, Zion National Park, Utah
- 9-cent orange, Mount Rockwell and Two Medicine Lake, Glacier National Park, Montana
- 10-cent gray black, Great Smoky Mountains National Park, North Carolina
Two imperforate souvenir sheets were issued with designs from the National Parks Series. A souvenir sheet of six 3-cent stamps was issued on August 28, 1934, for the American Philatelic Society Exhibition. A souvenir sheet of six 1-cent stamps was issued on October 10, 1934, for the Trans-Mississippi Philatelic Exposition.
The National Parks Series was reissued on March 15, 1935, in imperforate, ungummed sheets of two hundred, and in imperforate, ungummed sheets of twenty panes of six stamps each. Referred to as 'Farley's Follies', Postmaster General James Farley's 'special printings' suffered a storm of criticism. It boiled over with this excessive issue. Farley was pilloried in both the philatelic and the popular press. He finally abandoned the practice. The National Parks series was the last of the special printings.
Gordon T. Trotter