BOSTON (CBS) – It was a sight they’ll never forget.

Two co-workers from Massachusetts who took a sightseeing break during a business trip to Arizona last month ended up with a 120-pound boulder between them in the front seat of their car.

The boulder in the front seat after the accident. (Photo courtesy: Bob Jaczko)

Peter Wilson of Attleboro and Bob Jaczko of Natick had followed the advice of a tour guide and went to see Oak Creek Canyon.

“We visited a Catholic chapel, threw pennies in a magic stream and then went to the crystal shop. We had all this mysticism around us so I think we were well protected,” Jaczko told WBZ-TV.

As they were driving back to their conference in Phoenix, a boulder fell from the canyon wall and crashed through the windshield of their car. It pummeled the dashboard then bounced off the center console before landing on Jaczko’s left shoulder. Both men were covered in glass.

Outside the car after the boulder hit. (Photo courtesy: Bob Jaczko)

“It shattered into a million little razor sharp slivers all over us,” Jaczko said.

“The boulder entirely ripped out the dashboard controls and all its electronic dials and wires in our laps and then totally smashed the shift console, throwing the car into immediate park. Imagine the speed and weight – it was over in a flash.”

A wide view of where the boulder fell onto the car. (Photo courtesy: Bob Jaczko)

Fortunately, two nurses were in cars behind them and helped them out until an ambulance arrived. One nurse used her baby’s diaper bag to clean Jaczko’s cuts and stop the bleeding.

Both men were treated at a local hospital. With their rental car inoperable, the hospital sprung for a limo to drive them the two hours back to Phoenix. There, the men finished their trade show.

“We were the talk of the trade show! We had a very crowded booth which was good for publicity. But I think I’ll do something different next time!”

WBZ-TV’s Bree Sison contributed to this report.

You can follow her on Twitter at @BreeSison.