Synchronous Fireflies light up the forest at dusk. (NPS Photo) Updated: May 7, 2025
Synchronous Fireflies Viewing Event
With over 2,000 species found world-wide, there are only three species of synchronous fireflies that can be found in North America. Every year, Congaree National Park hosts synchronous fireflies for approximately two weeks between mid-May and mid-June. During this time visitors can experience an awe-inspiring display of synchronous flashing while the fireflies search for a mate. This special and unique phenomenon is extremely popular. Below you will find information about this year's event, the lottery, park access during the synchronization period, and important guidelines for those coming to see these flashy fliers light up the night.
Park Operations During Firefly Viewing Event
This year’s viewing event for the synchronous fireflies will take place from May 14-21. During this time, the park will be operating under a modified operational schedule to allow staff time to transition from regular day-use visitor operations to special event operations during the evenings. Below is important information for anyone planning to visit the park during this time:
Beginning May 13 through the end of the event, all day-use visitors must be off park trails and must be out of the parking lots and have exited the park by no later than 4:30 p.m.
Entry to the park after 4:30 p.m. during the synchronous firefly viewing event requires a valid event pass, issued by recreation.gov. Those without a valid event pass will not be permitted entry that evening.
Event passes are valid only for the date and individual listed on the pass. Passes will only scan once and any subsequent attempts to use the same pass will show as invalid.
Gates will open to entry for those with valid event passes beginning at 7:00 p.m. and will remain open until 8:30 p.m. on event nights.
Firefly Viewing Event Lottery Information
Passes will be required to enter the park on event nights and will be awarded through a lottery system hosted through Recreation.gov.
This year’s pass lottery has closed.
Entries must be made through the online lottery page at https://www.recreation.gov/ticket/facility/300008 and are limited to one per household. All lottery applicants will be charged a $1 non-refundable service fee upon entering the lottery. Applicants who are awarded passes will be charged the remaining $19 event fee to secure their pass, for a total cost of $20. A total of 145 passes will be available for each event night. All applicants will be notified on Wednesday, April 16 whether they have or have not been awarded a pass.
Passes will admit one passenger vehicle with up to 2 axles that can fit in a standard parking space. During the event, vehicles such as RVs, vehicles with trailers, large passenger vans, buses or mini-buses, will not be admitted. Vehicles may have a maximum of 8 passengers. Passes may only be used one time, are only valid for the date listed. Passes are non-transferable. Gates on event nights will open for those with valid event passes beginning at 7:00 p.m. and close to entry at 8:30 p.m.
PLEASE NOTE: All questions or technical assistance requests concerning the lottery should be directed to Recreation.gov (877-444-6777), as the park does not manage the lottery system.
Park Closures During Firefly Synchronization
To best protect critical firefly habitat and allow park staff and volunteers to prepare for the event, certain areas of the park will be closed to all visitors at 4:30 p.m. daily. During this period the following areas will be closed:
The Harry Hampton Visitor Center, boardwalk, and frontcountry hiking trails.
Bannister Bridge Canoe Launch.
Cedar Creek between Bannister Bridge and South Cedar Creek Canoe Launch.
Longleaf and Bluff Campgrounds
Additionally, no backcountry camping permits will be issued during the period of the viewing event.
Basic Fireflies Event Etiquette and Information
Because these fireflies need specific habitat and conditions in order to synchronize, Congaree is one of only a few places where these conditions are present, and that visitors can experience this natural wonder. In order to provide you and fellow visitors with the best experience and to ensure there are fireflies for the future, please remember the following:
Keep flashlight use to a minimum, and only use lights that have a red-mode or have a red filter.
Keep all flashlights, when in use, pointed at the ground.
Cell phones may not be used in the viewing area for either a light source or taking photos/video.
No pets are permitted in the park during this event. Service animals are welcome.
All visitors should stay on the designated Firefly Trail.
Catching or disturbing fireflies is not permitted at Congaree National Park.
No insect repellent can be applied after arrival at the park. Please apply prior to arrival.
Viewing the fireflies is best just after dark, usually between 9:00 p.m. and 10:00 p.m.
Thunderstorms often occur during this time, so be prepared for the weather. Rain can slow down or stop firefly activity for the evening.
