Overview: Synchronous fireflies ( Photinus carolinus ) are one of at least 19 species of fireflies that live in Great Smoky Mountains National Park and one of only a few species in the world known to synchronize their flash patterns. This insects' reproductive display occurs for a couple of weeks every year throughout its range (southern Appalachians), and is typically in late May or early June in the Elkmont area of the park. During the peak firefly display period, the park organizes a shuttle service from Sugarlands Visitor Center to the Elkmont viewing area where a large population of synchronous fireflies occurs. Visitors who wish to view the fireflies must acquire a parking pass for the Sugarlands Visitor Center and ride a shuttle to the viewing area. The number of parking spaces is limited, as is the capacity of the shuttle system. During the 8-day shuttle operating period, the Elkmont area will be closed at night to all but the shuttle system and campers. Visit the park's Synchronous Fireflies web page for additional information about the event. Lottery for Parking Passes Parking passes are distributed via a lottery. This provides an equitable opportunity for interested visitors to obtain a pass for this limited, yet high-demand event. You must enter the date you would like to attend and you may choose one alternate date. Entering the lottery is free of charge. Lottery winners will be charged $20.00 and awarded a parking pass. There are no refunds, transfers, rain checks or changes to the parking pass. Lottery winners must occupy the vehicle and must present photo identification, which matches the name of the lottery winner, before the vehicle is admitted to the parking area. Only one application per household will be accepted. Regular Parking and Large Vehicle Parking Passes There are two types of vehicle passes: Regular Parking Pass - admits one passenger vehicle up to 19' in length and a maximum of 6 occupants Large Vehicle Pass - admits one large vehicle (RV, bus, etc) 19' to 30' in length, and a maximum of 24 occupants A total of 1800 vehicle passes will be distributed for the eight-day event (225 per day): 1768 Regular Parking Passes and 32 Large Vehicle Passes. Lottery applicants must apply for either a Regular Parking Pass OR a Large Vehicle Pass. Shuttle System - Per Person Fee and Trolley Schedule The shuttle fee is $2.00 per person, roundtrip (cash only) and must be paid when boarding the trolley. Please bring exact change. The first shuttle will depart the parking lot at approximately 7 p.m. The shuttles begin returning from Elkmont when filled to capacity, which will likely be after 9:30 p.m.; and they will continue running until everyone has been accommodated. Visitors should expect to return to their vehicle three to six hours after arriving at Sugarlands. The shuttle system may be cancelled if weather presents a threat to public safety. Viewing Area The viewing area at Elkmont is comprised of small paved areas and easy walking trails within a quarter mile of the trolley station. Rangers will be in the area to provide information. Please help protect the fireflies and their habitat by reviewing Light Show Etiquette. The viewing area and shuttle stop is a natural, outdoor environment with no shelter. Though the event may be cancelled if hazardous weather seems likely, participants should be prepared for the possibility of inclement weather.