The Letort Spring Run is an internationally renowned wild trout stream and is designated as a Pennsylvania Scenic River. The cold, clean water in this spring-fed stream produces nearly 20 times more aquatic life per acre than typical streams found outside limestone areas. The unique aquatic plants present in the Letort support large populations of aquatic insects, such as mayflies and midges, as well as crustaceans, including sowbugs and freshwater shrimp. These abundant organisms provide a rich food source for the famous Letort brown trout.

The wetlands surrounding the Letort Spring Run act as a buffer between upland areas and the stream. They recharge and discharge groundwater, store floodwater, trap sediment, remove pollutants, and stabilize stream banks. Additionally, these wetlands offer food and shelter for a diverse array of wildlife. While enjoying the nature trail, visitors are likely to encounter white-tailed deer, red foxes, wild turkeys, migrating songbirds, geese, ducks, herons, and more.

Letort Spring Run is just under 10 miles long and serves as a tributary of the Conodoguinet Creek. The stream generally measures about 20 feet between its banks, but in some areas, the soft bottom can plunge fairly deep, so waders must remain cautious. The stream runs through Letort Spring Park and flows into Carlisle City just below the park.

Recognized in the popular publication “50 Places to Fish Before You Die” (Santella, 2012), Letort Spring Run offers a rewarding challenge for anglers. Its clear, high-quality waters make it easy for fish to spot threats, but skilled fishermen might just catch “the big one.” The stream is home to record-setting brown trout, making it a dream destination for fly fishers.

Experts recommend casting from the lower areas of the stream, where the water is wider, rather than the upper regions, which have thicker vegetation. Gentle runs and riffles in the stream create excellent spots to catch trout. The spring-fed waterway remains cool even during the hottest summer temperatures. A 1.5-mile stretch between Route 481 and the Reading Railroad Bridge is designated for catch-and-release fishing only, where the trout are typically very large.

Seasoned fly fishers recognize the names of Charles K. Fox, Vincent, Ed Koch, and Ed Shenk, who have all pioneered techniques and fly patterns essential to modern fly fishing along the banks of the Letort. Fly fishing with floating terrestrials and midges was developed here as well.

The section of Letort Spring Run adjacent to the Letort Nature Trail was the first special regulation area in Pennsylvania to limit angling techniques and establish catch-and-release fishing. Stream habitat improvement practices that are both minimally invasive and aesthetically pleasing have been implemented along the Letort Spring Run.

Catch-and-release fly fishing continues as the only authorized method of fishing upstream of Letort Park. However, all legal fishing techniques are permitted in the park and downstream to the Letort’s confluence with Conodoguinet Creek in Middlesex Township. The special-regulation area is easily accessible because the Letort Nature Trail runs parallel to the stream for most of its length. Access points are also available in Letort Park and Biddle Mission Park in Carlisle. From Biddle Mission Park downstream, much of the Letort is bordered by private property; however, persistent anglers will find numerous access points.

Please respect property owners’ privacy and always obtain permission before entering anyone’s yard. Letort Spring Run has a reputation for being a very challenging stream to fish. Stream-bred brown trout are wary, and the water flows slowly and smoothly for most of its course, giving the fish an advantage. Wading can be especially challenging due to heavy silting in many areas, so most anglers fish from the banks. Catching one of the Letort’s wild trout measuring over 12 inches is considered a significant accomplishment.