Kansas City, Mo. ? Boulevard Brewing Co. has canceled an advertising campaign featuring the silhouettes of explorers Meriwether Lewis and William Clark after receiving protests from the National Park Service, which owns the copyright of the image.

Kansas City-based Boulevard canceled the campaign Wednesday and will destroy about $15,000 worth of metal signs bearing the image of the explorers, with one of them holding a bottle of Boulevard Pale Ale rather than pointing a finger west. The signs were to be shipped this week to restaurants, bars and liquor stores in several Midwestern states.

“Everybody who had seen our graphic had been so excited,” said Bob Sullivan, a Boulevard vice president. “But Boulevard is not going to partake in any kind of use that is inappropriate or unauthorized. The bottom line is that we are not going there.”

Meanwhile, the advertising agency behind the campaign, CHRW of Kansas City, is developing a new Lewis and Clark likeness for Boulevard, whose beer is available in Arkansas, Iowa, Illinois, Kansas, Missouri, Nebraska, Oklahoma, South Dakota, and the Twin Cities area.

The image in question is seen frequently on the highways of states that the explorers visited 200 years ago.

CHRW thought it had performed due diligence by purchasing $3,000 worth of images, including one of a Lewis and Clark road sign, from Corbis Corp., a photography archiving company.

“We figured that as long as we’re paying … we were good,” said Jeremy Ragonese, a CHRW partner.

Richard Williams of the National Park Service in Omaha, Neb., said the agency didn’t do enough.

“Just because somebody purchased the image from a Web page doesn’t mean they own the image,” he said.

The logo, Williams said, is a federal insignia, protected by copyright law and federal statute. Any commercial representation of it would suggest federal government endorsement of a product, he said.

“We have nothing against the product, but that is the regulation,” said Williams, manager of the Lewis and Clark National Historic Trail.

The logo, adopted by the National Park Service in 1978, is based on a 1960s painting now owned by the Lewis & Clark Trail Heritage Foundation of Great Falls, Mont.