Tolka Valley Park is an important regional park located on both sides of the Tolka River between Pelletstown, Finglas and Glasnevin, in Dublin City. The park is spread over 140 hectares and follows the Tolka River Valley for 8km from Mulhuddard to Ashtown. The pasturelands and playing fields of the upper section give way to woodlands, undulating fields and wetlands, providing varied landscapes and natural habitats for a wide range of fauna. The river valley is rich in plant and animal life, a haven for biodiversity within the city, and local history. The park is situated over a former city landfill, creating challenges to its management and design. There is an elevated boardwalk opposite the town centre, Blanchardstown, a viewing bridge and a variety of playing pitches.

One of the interesting projects here is the ‘integrated constructed wetlands’ which were created in 1999 as a novel way of treating the incoming waters of the Finglaswood Stream. The construction of the wetland has been a success on many fronts: trapping pollution, reducing bad odours, making the pond more pleasant, and creation of new wetland habitat for local biodiversity. Perhaps the most exciting species here is the common frog rana temporaria (listed as ‘Internationally Important’ in the Red Data Book). The wetlands at Tolka Valley Park can be seen to be making a valuable contribution to the conservation status of this important species in Europe.