What you will see
Archeological artifacts, Restrictions, Sea Life, Wreck
The Roberto Ivens minesweeper is an old trawler requisitioned by the Portuguese Navy during the Great War.
He sank on 26th July 1917, about 4 nautical miles South of the Bugio Lighthouse, at the mouth of the Tagus river. It collided with a mine that it did not detect, left days earlier by the German imperial submarine UC54.
This wreck was long known to fishermen, but it was not until 2016 that it was identified as the Roberto Ivens minesweeper whose shipwreck was believed to have occurred in a distinct location, 12 nautical miles South of the town of Cascais.
The wreck lies on a flat sandy bottom, 36mts deep.
Originally about 44mts long, the stern exploded with the bursting of the mine, so from the boilers to the rear you can only see a silvery field of wreckage. Located almost at the entrance to the port of Lisbon, it is exposed both to the prevailing currents and winds of the West and South, and to the strong current of the river Tagus, which carries lots of sediments.
It is only advisable to dive into this wreckage on high tides, to try to find better visibilities. But this is not always possible due to the Atlantic conditions that are often felt on the Portuguese coast. Therefore, despite its relevant historical value, this wreck is not so popular among divers.
--Spot description by Paulo Costa