At the northern end of the Adriatic where the river Timavo enters, there begins a sterich of coastline characterized by shallow water and a complex structure of lagoons, including the Lagoon of Venice, which goes right down to the delta of the river Po. Near the mouth of the river  Timavo is that of the river Isonzo which rises in the Julian Alps in Slovenia and wends its way down to enter the Gulf of Trieste between the towns of Monfalcone and Grado . The Isonzo Rivermouth Nature Reserve covers an area of approximately 2400 hectares  situated along the final 15 km of the course of the river. The reserve is located  within the municipalities of Staranzano , S. Canzian d’Isonzo and Fiumicello.
The Isonzo Rivermouth Nature Reserve offers the possibility to study a wide range of interesting animals, often belonging to species which are rare or unusual elsewhere. The birdlife is constantly monitored, and thus far more than 300 species of birds have been recorded. Of these, some are migrants and choose the area as a stopover  on their long migrations, whilst others winter in the area. Another group spend the summer months on the reserve. There are a large  numbers of species of ducks and geese but one can also observe coots, herons, curlews and several species of birds of prey. As far as the mammals are concerned, thanks  to the peacefulness of the place and its closeness to the limestone Karst, one can find a good number of species including the roe deer, the fox, the badger, the wild boar, the hare as well as numerous species  of rodents, bats and insectivores.  Some Camargue horses have been brought to the site, a breed which, for its physical  characteristics is especially adapted to life in wetlands.