SAN FRANCISCO (KGO) -- Security is being stepped up at the Golden Gate Bridge after an alarming video of two Wisconsin teens climbing to the top of the north tower.
FULL VIDEO: Daredevils climb to top of Golden Gate Bridge
They didn't have ropes, harnesses, or safety gear, and they were able to get up there without alerting security.
When they got to the top, they didn't just take in the view, they did somersaults and back flips.
Bridge security officials say they made immediate changes including upgrading motion sensors and adding patrols.
"They're pretty steep, you have to grab on to the sides and I had to do it with one hand because I had my camera in one hand," Teatime said. Teatime says he and a buddy came to the bay area for spring break last month and decided to climb the bridge at 3 a.m.
A bridge spokesperson says the structure itself was never in any danger. "Where these individuals were and what they were engaged in would not have harmed the bridge, so it did not trigger alarms," Denis Mulligan said.
The CHP and Homeland Security are both investigating. The teens could face up to a year in jail and fines up to $10,000.
Click here for the full interview with the two teenagers who climbed the bridge.