| |  | LET'S GET TECHNICAL! For 90 years, Cortland has been making high quality fishing lines for anglers throughout the world. We are now in our fifth decade of producing the fly lines that are generally considered to be the finest in the world. The following pages are intended as an educational guide to Cortland lines. We touch briefly on line configuration, construction, taper designs, AFTMA standards and sinking rates. We then provide the actual specifications for each line we make. Technical Info: Click below for a magnificent overview over the range of fly lines we offer: Fly Line Specifications: Frequently asked questions | | | U.S. STREAM CONDITIONS | Recent data provided by the USGS in USA -- including stream discharge, water levels, precipitation, and components from water-quality monitors--are preliminary and have not received final approval.... U.S. Stream Conditions  | |