The Letort is among the most famous of all Pennsylvania trout streams. It is a stream that requires technical skill in still-water and a great deal of patience. The upper section of the Letort is catch-and-release and is known for its population of wild brown trout. Hip waders are recommended.
| Month | Fly | Size |
| December-January | Woolly Buggers Sculpins Nymphs | 8-12 6-12 14-18 |
| February | Woolly Buggers Sculpins Cress Bugs Midges | 8-12 6-12 14-18 20-26 |
| March | Sculpins Midges Cress Bugs | 6-12 20-26 12-16 |
| April | Blue Winged Olive Midges Sculpins Cress Bugs | 18-20 20-26 6-12 12-16 |
| May | Blue Winged Olive Midges Sculpins Sulphurs Cress Bugs | 14-18 20-26 6-12 14-18 12-16 |
| June | Blue Winged Olive Sculpins Sulphurs Cress Bugs | 16-20 6-12 14-16 12-16 |
| July | Tricos Cress Bugs Ants/Beetles Sculpins | 20-24 12-16 12-18 6-12 |
| August | Cress Bugs Ants/Beetles Tricos | 12-16 12-16 20-24 |
| September | Cress Bugs Ants/Beetles Hoppers/Crickets Tricos | 12-16 12-14 8-12 20-24 |
| October | Sculpins Tricos Hoppers/Crickets Cress Bugs | 6-10 20-24 8-12 12-16 |
| November-December | Cress Bugs Sculpins Midges | 12-16 4-12 20-24 |