This year's dates for the ever-popular firefly viewing event at Elkmont in the Great Smoky Mountains National Park are May 31-June 7, according to park officials.

Parking passes will be distributed this year through a lottery system administered through As in previous years, access to the viewing area will be limited to shuttle services between the Sugarlands Visitor Center and Elkmont.

The eight-day viewing event is scheduled to coincide with the peak mating activity of the park's synchronous fireflies (Photinus carolinus). The distinctive flashing is a result of the male fireflies signaling their presence to the females.

All visitors wishing to view the fireflies must have parking passes distributed through the online lottery. The lottery opens Friday at noon and runs through Monday at 8 p.m. Results will be available on Tuesday.

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