It's just a wide spot on Colorado 93 now, but 30 years ago the Rocky Flats Nuclear Weapons Plant loomed just over the horizon.

In concrete buildings behind steel fences and barbed wire, workers assembled triggers for nuclear weapons.

"This spot is really a sacred place for us," Pat McCormick, a sister of Loretto, said Sunday of the place in unincorporated Jefferson County where workers entered the plant each day.

McCormick came here every Sunday for 12 years beginning in the late 1970s to pray for an end to war and nuclear weapons.

"We prayed and asked God for the courage to resist," McCormick said.

Rocky Flats was demolished in the late 1990s after federal officials determined it was no longer needed and that it would require extensive safety improvements for further use as a nuclear plant.

On Sunday, McCormick was among 50 people, many of them elderly, who came to the former plant entrance to remember the anti-nuclear movement.

The gathering, as well as events on Friday night and Saturday, commemorated the first major protest at the plant gate in April 1978.

Initially peaceful, it was followed by efforts to disrupt the plant that lasted through the mid-1980s and included many arrests.

"There's nothing nostalgic about it," McCormick, 72, said of the gathering.

She's acutely conscious that the anti-nuclear movement did not succeed in eliminating the weapons.

A handful of the participants marched Sunday from downtown Boulder, but most arrived in cars.

Like McCormick, many of the former protesters revere this spot.

The ashes of two protesters are scattered in the area, said LeRoy Moore, a longtime leader of the Rocky Mountain Peace and Justice Center, which was formed in Boulder during the protests.

"The (security guards) would allow us to be on the other side of that fence there," said Tom Morris, 58, pointing to what used to be a barrier, but now can be walked around.

"Some people would fast there and spend days there. A Buddhist monk, I think, did a 50-day fast."

Morris, who worked as a tofu maker and later owned a health food store, said he would chant for eight hours at a time.

"On a personal level it was really a deep experience to sit here in all kinds of weather and under all kinds of adverse conditions in terms of workers yelling at us," Morris said. "Drivers whizzed by on the highway yelling at us."

"So, through all that, you would sit and chant and just persevere. It was just such a lesson personally in how to overcome adversity and stay true to what you're doing."