The Postal Service issued the 39-cent Wonders of America: Land of Superlatives commemorative stamps on May 27, 2006 in Washington, DC. The stamps, designed by Richard Sheaff of Scottsdale, Arizona, were produced in forty designs in a pressure-sensitive adhesive (PSA) pane of forty stamps.
This stamp pane features forty natural and man-made wonders of the United States. These remarkable places, plants, animals, and structures were selected from every region of the country.
On the front of each stamp, in large letters, are words that describe the superlative nature of a particular place or thing. Smaller type gives the name or location of the featured wonder. Text on the back of each stamp provides relevant statistics and information. The stamp art is by Lonnie Busch of Franklin, North Carolina.
Avery Dennison produced the 204 million stamps on the gravure press.
Postal Bulletin (April 27, 2006).