The River Park is a naturalistic path, about 2 km long, that connects the centre of Isola del Liri with the locality of Vadurso near the Abbey of San Domenico, on the boundary with Sora. The route, which runs along the banks of the Liri river, starts in the town centre from the Roma bridge and continues in the equipped green area where the Modesto Galante Municipal Library is located, among fountains and installations made from parts of the old paper mill machinery. From here it is possible to admire the Valcatoio Waterfall, 27 m high, whose waters partly feed a hydroelectric power station.

The path continues uphill beyond the building of the former municipal slaughterhouse, along the slope of the San Sebastiano hill until it reaches the dam near the Boncompagni-Viscogliosi castle. From here the path splits into two branches. On the right, it crosses a thick shrub vegetation close to the Liri river as far as the Remorici locality, where the remains of the former Ciccodicola wool mill can be found. Continuing until Viale Barca San Domenico, near the Sora Fair, there are the ruins of the 1st century B.C. Marmone Bridge and the confluence of the Fibreno and the Liri, near the Abbey of San Domenico.