WASHINGTON — Musicians Bonnie Raitt and Emmylou Harris, actor Christopher Reeve and artist Maya Lin are lending their faces and voices to a new public service announcement (PSA) effort by the Campaign for America’s Wilderness to help celebrate the 40th anniversary of the Wilderness Act, which was signed into law Sept. 3, 1964.

“When I’m not on the road doing concerts, there’s nothing I like more than getting out into the wilderness,” said Raitt in a radio PSA. “In wilderness, you can hear again the truest sounds of this country — “the call of a loon, the growl of a grizzly. In wilderness, you can feel the wind across your face, or dip your toes into clean, cool water from a mountain stream. It’s a part of what we share as Americans.”

The Wilderness Act — the nation’s conservation capstone — established the National Wilderness Preservation System and immediately protected the first 9 million acres of wild public land, including California’s John Muir Wilderness, New Mexico’s Gila Wilderness, Glacier Peak in Washington, Idaho’s Selway-Bitterroot, and North Carolina’s Shining Rock Wilderness.

Maya Lin, designer of the Vietnam Veterans Memorial in Washington, D.C., appears in one of the campaign’s print PSAs. “From skyscraping mountains towering from above, to prehistoric land bridges stretching far and wide — no human structure can ever match the natural magnificence of America’s wilderness. That’s why it’s so vitally important that we protect it.”

More than 106 million acres are in the National Wilderness Preservation System today, but this represents just 2.5 percent of America’s landmass outside of Alaska. While much has been accomplished, the PSA campaign reminds us there are more wild lands that merit protection.