Numerous massive square-based pillars can be found approximately 600 m from the shore at Lucrino. They were constructed in a combination of Roman masonry, particularly opus reticulatum, and, due to their location, are presumed to have provided protection to Portus Julius.

Their heights reach from the sea-bed at depths of up to 16m to several meters below sea-level. Thus, they provide considerable protection from prevailing currents whilst generating differing light parameters. This has resulted in their tops being covered with algae which gradually recedes with depth to reveal an environment typical of the Meditterranean. This spectacular combination provides a unique habitat for a wide variety of organisms which have adapted to shallower waters than those in which they would usually abide. Not solely on the pillars themselves but also between them where fallen stonework is to be found, numerous different species of fish and all manner of marine life have found refuge.

Returning to the location's name, emphasis must be given here to the geological aspect - active fumaroles are plentiful and attest the volcanic origin of this area. These fumaroles are columns of gaseous bubbles which escape from the sea bed (at temperatures higher than those ambient) depositing sulphur which covers the surrounding sea floor giving it a white fluffy appearnce.