When the drawbridge suddenly opened into the upright position, McGowan, 55, used her hands and feet to cling to the structure 22 feet in the air.
"She was just stuck in this Jesus Christ position," witness Phillip Glazebrook told the Sun-Sentinel.
"The woman was frozen and terrified."
Firefighters called to the scene used a 24-foot ladder to rescue her 20 minutes later.
"The woman was frightened but not injured," Fort Lauderdale Fire Rescue rep Matt Little said.
Police said railroad authorities are determining whether to press charges for trespassing.
"We are thankful that the individual involved in this life-threatening incident survived. The decision to trespass on private property was an unfortunate, poor choice that endangered the trespasser’s life as well as the lives of the first responders," Little added. "The decision to cross the clearly marked railroad bridge should not be lauded."
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