Synchronous Fireflies at Congaree

Fireflies at Congaree National Park along the Bluff Trail.
Fireflies along the Bluff Trail May 2016 (Photo used with permission; Frederick Austin)
Synchronized Fireflies (May-June 2018)

Updated March, 19 2018
Please note that the exact dates that the fireflies will synchronize in 2018 is not known. This phenomenon could occur earlier in May or later in June, but in general usually starts around the middle of May. Factors including soil conditions and temperature affect when this natural phenomenon occurs.

We will be posting additional information on this page as we get closer to "firefly season." All relevant information will be posted on this page as it becomes available.

Please be advised that this is the most visited event of the year for Congaree National Park and large crowds are very common. Please become familiar with the following information, which will help you and other visitors have an enjoyable visit.

Important Info & Viewing Etiquette
  • The Harry Hampton Visitor Center will be open for extended hours from Friday, May 11 through Sunday, May 20 (9:00am-10:00pm).
  • Dogs will NOT be allowed in the park after 5:00pm from Friday, May 11 through Sunday, May 20, due to the large numbers of people.
  • Setting up chairs, hammocks and/or blankets will NOT be allowed on or along park trails after 5pm from Friday, May 11 through Sunday, May 20.
  • If you are going to use insect repellent, please apply BEFORE entering the park. Insect repllent will adversly affect fireflies.
  • Please be considerate to other visitors viewing this phenomenon.
  • Because of the increased number of visitors, we ask that everyone keep noise levels to a minimum so that everyone can enjoy this special natural occurrence.
  • Use red filters on your flashlights. Bright lights can disturb the fireflies’ flash pattern and make it difficult for other people to see.
  • Do not use flash photography. The flashing can be difficult to capture on camera/video.
  • Parking is limited. Carpool when possible.
  • Bus and oversize vehicle parking will be very limited, so please plan to drop off passengers and have a set time to return to the park to pick them up. Parking for oversize vehicles is NOT guaranteed.
  • Be prepared for the weather.
  • Fireflies are only here for a few short weeks. Please do not capture them in jars or take them with you.
Many children remember catching fireflies in jars when they were young, but not all fireflies are the same. With over 2,000 species found world-wide, there are only three species of synchronous flashing fireflies that can be found in North America. Every year, Congaree National Park hosts synchronous fireflies (Photuris frontalis) 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. For information on the scientific research of fireflies at Congaree National Park, be sure to visit the Old Growth Bottomland Forest Research and Education Center's fireflies page.
The best time to view the fireflies is just after dark, usually between 9:00pm and 10:00pm. The best viewing is along the bluff. The boardwalk is a popular place to view them and they can also be seen along Bluff Trail and in Bluff Campground.
(Updated on March 19, 2018)

Last updated: March 19, 2018

Contact the Park

Mailing Address:

100 National Park Road
Hopkins, SC 29061


(803) 776-4396

Contact Us