Viikki-Vanhankaupunginlahti Nature Reserve is the most important nature reserve in Helsinki, and among the most valuable bird sanctuaries and conservation areas on the coastal Gulf of Finland.
The area is a mosaic of forests, alder marshes, fields and meadows. Plant and animal is abundant, which makes Viikki-Vanhankaupunginlahti bay a place of great interest for both researches and nature enthusiasts.
Viikki-Vanhankaupunginlahti bay area is one of the most popular recreational areas in Helsinki. Some of the area is also part of the EU Natura 2000 network.