Yosemite National Park has a pest problem: Ticket scalpers who are selling the limited camping reservations at exorbitant prices.
Spokesman Scott Gediman tells the Sacramento Bee that park officials are becoming more aggressive as they try to curb scalpers.
The nation's third-most visited park has only 900 reserved campsites available at any given time. They go for $20 a night but scalpers advertising on Craigslist are offering them for $100 or more — sometimes for hundreds of dollars.
They're also selling permits to climb Half Dome, which the park essentially issues for free.
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Gediman says it appears that some scalpers may have devised ways of jumping the reservation queue, possibly through automated computer programs that can instantly snag cancellations.