Get Ready for the Annual Firefly Light Show in the Great Smoky Mountains—Here’s How to Experience It

The Great Smoky Mountains National Park is preparing for its annual event featuring synchronous fireflies—the largest gathering of these enchanting creatures in the Western Hemisphere. During this magical time, swarms of lightning bugs will illuminate the park at night. Due to its popularity, a lottery system has been put in place to secure the sought-after parking passes needed to attend. Here’s how you can obtain one and what to anticipate.

Tips for Viewing the Synchronous Fireflies in the Great Smoky Mountains

In 2024, the lottery for viewing the synchronous fireflies in the Great Smoky Mountains National Park will open on April 26 at 10 a.m. EST and will close on April 29, 2024, at 11:59 p.m. EST. Interested participants can enter the lottery at Recreation.gov, with a $1 application fee required.

The viewing period for the synchronous fireflies in the Great Smoky Mountains in 2024 is set from June 3 to June 10. Lottery applicants will be notified about the acceptance or rejection of their applications around mid-May.

Lottery winners will automatically receive (and be billed for) the vehicle pass required to access the viewing area. The Great Smoky Mountains National Park will issue a total of 1,120 vehicle passes over the eight-day event (140 passes per day). Winners will pay $24 per vehicle and may bring up to seven passengers.

Participating in the event

Each pass is only valid for a designated date, and a specific arrival time between 6:00 p.m. and 8:00 p.m. will be assigned. No additional passes will be offered beyond those allocated in the lottery.

Attendees are required to cover their flashlights with red or blue cellophane to minimize disruption, turn them off once they've found a viewing spot, and remain on marked trails or paved surfaces at all times. Also, please refrain from catching fireflies—leave those Ball jars at home, everyone.

After checking in, parking attendants will guide vehicles to designated parking areas, allowing visitors to leave their cars during the viewing. A limited number of ADA parking spaces will be available on a first-come, first-served basis. The main viewing areas are the Jakes Creek and Little River trails.

What are synchronous fireflies?

Synchronous fireflies are a distinct species of firefly (also known as lightning bugs), capable of synchronizing their light displays. These flashing patterns, emitted from “lanterns” on their abdomens, play a role in their mating ritual, allowing males and females to identify each other. Males will fly and flash their lights, while the typically stationary females respond with a flash, as explained on the Great Smoky Mountains National Park’s dedicated synchronous fireflies page.

The reason behind the synchronized flashing of the fireflies remains a mystery, and they don’t always flash in unison. When they do, a burst of light is often followed by a sudden darkness.

The peak mating season lasts about two weeks each year, with display dates varying annually. Scientists predict these dates based on factors like temperature and soil moisture. Even during this peak period, the park warns that attendees may not always experience an optimal display, as environmental conditions such as rain or temperatures dropping below 50 degrees can halt the spectacle on any given night.

Other locations to witness synchronous fireflies in the USA

While the Great Smoky Mountains host one of the most famous firefly displays, other U.S. parks also feature synchronous fireflies each year. Though the lotteries for these parks have closed, those interested should mark their calendars for 2025.

Congaree National Park

The annual synchronous firefly viewing event at Congaree National Park is scheduled for May 16 to 25, 2024. Similar to the Great Smoky Mountains, attendees must secure parking passes through a lottery system to participate. The lottery opened on April 4 and closed on April 10, with winners being notified on April 16. Parking passes for this event are priced at $24 per vehicle.

Allegheny National Forest

Pennsylvania is home to 15 species of fireflies, with June being the best time to see them. The annual PA Firefly Festival occurs in Tionesta, set for Friday, June 28, and Saturday, June 29, in 2024. Registration for the 2024 lottery is now closed.

This article was initially published online in 2019 and was last updated on April 24, 2024, to reflect the latest information.