the valley floor, and opened for rail traffic in 1911. It was the largest concrete viaduct in the world until 1915, when the Lackawanna Railroad opened the Tunkhannock Viaduct in Nicholson, Pennsylvania, spanning over twice the Paulinskill Viaduct's length. Currently abandoned, several plans are underway by New Jersey Transit to open the route as a passenger line to Scranton, Pennsylvania. This site is commonly visited by adventure-seeking individuals. Today The Paulins Kill continues to maintain its rural character through both local concern and government policy. It is an excellent area for birdwatching, canoeing, hiking, hunting and fishing, and is considered to be one of the best trout streams in New Jersey. Fishing The Paulins Kill is a popular fishing destination for various species of trout, such as rainbow trout, brown trout and brook trout. Trout are stocked each year during the spring fishing season by New Jersey's Division of Fish & Wildlife. Hardly any wild trout are found. This is due to the river getting shallow in summer and warm. The river owes its fly fishing reputation largely to the prolific populations of various species of the mayfly and caddisfly.<ref>Music to a Hare's Ears by Henry Bell in Skylands Magazine, accessed October 29, 2006.</ref> Historically, the Paulins Kill was known to be populated with American shad, but with the construction of mill dams across the river in the eighteenth and nineteenth century, the shad were unable to spawn in the river. Shad can still be found in the Delaware River. Protected areas The Paulins Kill valley contains many protected areas. Swartswood State Park, established in 1914 as the first and oldest state park in New Jersey, is on just north of Paulins Kill Lake in Sussex County. Along Kittatinny Ridge in the northern part of the watershed are parts of Worthington State Forest (west), Delaware Water Gap National Recreation Area (central), and Stokes State Forests (east).National Park Service: Delaware Water Gap National Recreation Area, official website, no further authorship information given, accessed December 20, 2006 In addition to these state forests, the Paulins Kill valley is host to a variety of common coniferous and deciduous trees, which have been harvested for lumber in the past, including: white oak and black oak, buttonwood, eastern red cedar, eastern hemlock, American chestnut, black walnut, tamarack larch, spruce, and pine. Trees that add to the beauty of the fall foliage include maple, birch, hickory,