UFO's are famous in this area, as well as a rumor of an undersea ufo base.
From Here
Palma de Mallorca, Aug 05, 2002 (EFE via COMTEX) -- Sailors, skin
divers and fishermen have all heard them. Strange, persistent noises
from under the waters off Mallorca's northern coast. Nobody knows what
they are or who's making them.
Story Filed: Monday, August 05, 2002 5:05 AM EST
Palma de Mallorca, Aug 05, 2002 (EFE via COMTEX) -- Sailors, skin
divers and fishermen have all heard them. Strange, persistent noises
from under the waters off Mallorca's northern coast. Nobody knows what
they are or who's making them.
"It's this very shrill sound, like some distant machinery, but so
intense that you think wherever they're coming from must be only a few
yards away," EFE was told by Josep Amengual, a three-times scuba
fishing champion.
The noise can be even be heard if one's ears are just above the
surface when the sea is calm but is restricted to the zone between the
offshore islet of La Dragonera and Cape Formentor, on the northwestern
coast of the largest of Spain's Balearic island chain.
That much is all the Palma-based Center for Undersea Research and
Activity says it is prepared to confirm, though it admits its staff
knows of no precedent for the phenomenon reported by dozens of its
members.
Another scuba fisherman, Toni Carbonell, said "it repeats itself every
six or seven seconds and makes a noise like what a giant metal tube
would make if it were to fall from a height onto the ground".
At least one fish species appears to be bothered by the disturbing
noises but seasoned fishermen who ply these waters say there has been
no major change in the quantity or type of catch they have been
hauling in over the past few months.
Totally tentative explanations being put forward to account for the
mystery noise include underwater oil prospecting on Spain's coastal
shelf near Tarragona, some 500 kilometers (350 miles) distant, to
construction work going on somewhere further along the north coast of
Mallorca.
As it happens, since the early 1970s that same stretch of coastline
has been the site of repeated UFO sightings, and published reports
dating as far back as 1978 claim that flying saucers were spotted
emerging from an undersea base off the town of S]ller.
Saucer buff Mat]as Morey said that long before the noises were
detected, several "experts" had demonstrated grounds for concluding
that an undersea UFO base existed some 1,000 to 1,500 yards offshore
between Punta Cala Roja y Es Morro de sa Vaca.
On the other side of are those who insist all that is needed is for
the Mallorcan research center to be given the funding needed to record
the sounds and access the professional expertise and equipment
required for a detailed analysts of its characteristics
"There's no such thing as an inexplicable phenomenon," says Joan
Miquel Batle, an expert on undersea acoustics. "Everything has a
logical, scientific explanation, it's just that sometimes we don't
know what it is."