Thousands of Fireflies Will Create a Spectacular Light Show in the Great Smoky Mountains

Each year, countless lightning bugs converge on the national park, flickering among trees in one of the country’s most scenic forests. Details about how to get access (a limited number of people can attend) have just been released.

Thousands of Fireflies Will Create a Spectacular Light Show in the Great Smoky Mountains

Synchronous fireflies are a unique species that actually coordinate their light display.

Photo by WUT.ANUNAI/Shutterstock

The Great Smoky Mountains National Park is gearing up for its annual synchronous fireflies event, during which swarms of lightning bugs will light up the park at night. The once-a-year phenomenon is so popular that a lottery system has been established for obtaining the coveted parking passes required to attend.

This year, the lottery for the parking passes to see the fireflies opens on April 29, 2022, at 10 a.m. EST and will close on May 3, 2022, at 10 a.m. EST. You can enter the lottery at Recreation.gov. The event will run from Friday, June 3, through Friday, June 10, 2022.

For $24 per vehicle (seven passengers maximum), successful lottery applicants will automatically obtain the vehicle pass necessary to access the Elkmont viewing area, where the largest gathering of synchronous fireflies in the Western Hemisphere occurs. After visitors check in near the Elkmont Campground Kiosk, parking attendants will direct vehicles into designated parking areas, where visitors can then leave their vehicles for viewing. A designated number of ADA parking spaces will be available on a first-come, first-served basis. Primary viewing areas are Jakes Creek and Little River trails.

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The firefly display takes place in the Elkmont section of the Great Smoky Mountains National Park.

Photo by William Silver/Shutterstock

So, what are synchronous fireflies, exactly? They are a unique species of firefly (a type of beetle also known as a lightning bug) that can actually synchronize their flashing light displays. Their light patterns, which are produced in their “lanterns” along their abdomens, are part of a mating ritual that helps males and females recognize each other. The males will fly and flash their light and the typically stationary females will respond with a flash, according to the park’s dedicated synchronous fireflies page.

No one is exactly sure why the fireflies flash their lights in unison, and they don’t always do so. When they do, a burst of light ends with an abrupt period of darkness.

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Fireflies’ bioluminescent lanterns are tucked into their abdomens.

Photo by Suzanne Tucker/Shutterstock

The peak mating season lasts for approximately two weeks each year, and the dates of the display vary from one year to the next. Scientists predict the dates based on factors such as temperature and the moisture in the soil. Even during the peak season, attendees aren’t guaranteed a perfect display, the park has cautioned. Environmental factors such as rainfall or cooler temperatures that fall below 50 degrees can shut down the display on any given night. Nevertheless, those who would like to try their luck at having the rare chance to see the annual phenomenon will need to enter the online lottery by May 3. A total of 800 vehicle passes will be distributed for the eight-day event (or 100 per day), with no vehicle to exceed seven passengers.

Lottery applicants will be informed via email on Thursday, May 12, about whether they have successfully obtained a vehicle pass. Each pass is valid only for a specified date, and an arrival time between 6:00 p.m. and 8:00 p.m. will be assigned. Lottery winners will automatically be charged a $1 application fee and $24 vehicle fee. No additional passes beyond those assigned during the lottery will be made available.

Attendees are asked to cover their flashlights with red or blue cellophane so that they don’t disrupt the viewing experience and to turn them off altogether when they have found a viewing spot. They are also asked to stay on designated trails or paved surfaces at all times, and to not catch the fireflies, so leave those Ball jars at home, folks!

Other places to see fireflies this spring

While the Great Smoky Mountains may have one of the most well-known firefly displays, these other U.S. locations also welcome synchronous fireflies each year:

Congaree National Park

This year’s annual synchronous firefly viewing event at Congaree National Park will take place from Friday, May 20, through Sunday, May 22, and Friday, May 27, through Sunday, May 29. Similarly to Great Smoky Mountains, visitors need to win parking passes via a lottery system to attend. The lottery opened on March 31, 2022, at 10 a.m. EST, and closed on April 6, 2022 at 10 a.m. EST. Winners were notified on April 14. Parking passes cost $20 per vehicle for this event.

Allegheny National Forest

There are 15 species of firefly in Pennsylvania, and June is prime time to see them. The PA Firefly Festival takes place annually in Tionesta and is scheduled for Friday, June 24, and Saturday, June 25, in 2022. Registration for the event opens May 1 at 9 a.m. EST, and spots are limited. It costs $50 per person to attend and is free for children under 12.

This article originally appeared online in April 2019; it was most recently updated on April 26, 2022, to include current information. Rosalie Tinelli contributed reporting.

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Michelle Baran is the senior travel news editor at AFAR where she oversees breaking news, travel intel, pandemic coverage, airline, cruise, and consumer travel news. Baran joined AFAR in August 2018 after an 11-year run as a senior editor and reporter at leading travel industry newspaper Travel Weekly.
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