Those American hikers in Iran aren’t the only ones to get arrested for wandering too close to something a government says is high security and off-limits.

Exactly thirty years ago, five of us got arrested for hiking close to the Diablo Canyon Nuclear Power plant, located near San Luis Obispo California.

Thousands protested the Diablo Nuclear Plant in 1981–including a few hikers.

In September 1981, many thousands of anti-nuclear activists assembled at the plant’s entry gate, about seven miles from PG&E’s nuclear facility. Under the leadership of the Abalone Alliance, a California conservation group, they were attempting a human blockade to halt the start-up of the shoddily constructed plant, built on an active earthquake fault.

While nearly all the protesters, plant security, local police and national guard were squaring off at the plant gates, I and four fellow hikers tramped through miles of rugged backcountry almost to within a stone’s throw of Diablo’s reactors.

Our point was that the plant’s security could be easily breached and that the nuclear plant was vulnerable to potential saboteurs and crazy terrorists. We were able to find our way undetected to the plant with nothing more than a topo map and compass. The only obstacle we hikers encountered was a whole lot of poison oak.

Rock star Jackson Browne was arrested in the 1981 Diablo demonstration.

We surrendered peacefully to a platoon of National Guardsmen. The soldiers handcuffed us and hauled us off to jail. Actually, the jails were full to the brim with protesters, so we were incarcerated three days for our trespass in the Cuesta Community College gymnasium along with a couple of hundred other men, including rock star Jackson Browne.

We were the only hikers arrested, but all in all some 1,960 protesters were arrested during the ten-days of demonstrations at the gates of Diablo. The protest was viewed at the time, and is often still viewed, as the most significant anti-nuclear demonstration ever held in the United States.

For the vast majority of the protesters like me it would be the only time we would ever get arrested for civil disobedience—or for anything else for that matter.

(On the last day of the protest, PG&E disclosed that workers had mistakenly switched blueprints with Reactor One and Reactor Two; therefore all of the seismic safety systems had been built incorrectly. More embarrassing miscues followed, the Nuclear Regulatory Commission halted the low-power testing of the plant, and it would be several more years of construction and contentious hearings before the plant was allowed to open.)

An abbreviated account of the episode is in “A Canyon Called Diablo,” a chapter in my book, A Walk Along Land’s End: Dispatches from the Edge of California on a 1,600-mile Hike from Mexico to Oregon