Continuing from Trieste along the coastal road, just before the tunnel of Grignano we come to via Piccard, which leads to this special beach by going down the cul de sac on the left.
At the end of this track, just follow the steps on the left and you will find yourself on a pebble beach where fresh water currents flow. These are the fresh waters that gush from one of the underground branches of the River Timavo, and are collected in the 19th century building clearly visible from the small harbour and commonly called the Castelletto.
Here a complex system of underground tanks and pumps collects water from pools that, after passing through various filters, is purified (hence it is thought comes the name of the beach) and goes to supply the city.

Point of interest
The Castelletto filters were first built in 1854 to supply water to the steam locomotives of the Trieste-Vienna railway line, which was vital for the trade of the Austro-Hungarian Empire. For this reason, the strategic location and its equipment were manned by an entire artillery company until 1915.