Equally breath-taking from the spring in the magical village Kotle to the mouth in the bay near Novigrad
Descending in waterfalls over rocks and creating ravine pits in the rocks by which the village was named Kotle, Mirna starts its long, winding path through the green valley, bringing life to settlements of central Istria.
Mirna used to be navigable all the way to the port Baštija underneath Grožnjan, and with smaller riverboats it was possible to reach the citadel Pietrapelosa, almost next to the Buzet fortress. After several centuries the riverbed lifted up and it was possible to sail solely with flat-bottom boats. The riverbed was then deepened again by the Venetian Republic in order to make it possible to transport woods from the nearby Motovun forest.
Today Mirna has a completely new artificially made riverbed. The river traffic has ceased completely and now its natural beauty is revealed due to the settlements in its valley which are favourite tourist destinations in central Istria.