New National Park Service stamps unveiled in Pullman

CHICAGO (WLS) -- The only national park in Chicago is helping honor other parks around the country.

The Chicago Post Office helped unveil a sheet of stamps recognizing the National Park Service's 100th anniversary.

The ceremony was held at the Pullman National Monument, which became Chicago's first national park last year.

The sheet features images from 16 other parks and monuments from around the country. The stamps are on sale now.