Third year of MSP tours receive extra boost from TV show

Visitors tour the gas chamber at the Missouri State Penitentiary.
Visitors tour the gas chamber at the Missouri State Penitentiary.

More than 17,000 people toured the Missouri State Penitentiary in 2011. That's 47 percent more than in 2010.

This year was a trial-run for paranormal tours, which yielded attendance of more than 3,000 visitors. That's roughly equal to the total number of visitors for all history tours the first year in 2009.

The history tours remain in greatest demand, though, with more than ....