Battlefield Archaeology: A WW2 Oropesa Sweep in Paros island, Greece

By Pierre Kosmidis

Photos submitted by Markos Danezis 


Mine sweeping operations, following the end of World War 2, were absolutely necessary, as the Greek Seas were literally infested with thousands of sea mines laid by both Axis and Allied forces, in order to sever the vital sea routes from mainland Greece to the islands.


The task was of gigantic proportions and involved combined efforts of the post-war Greek navy, using specially developed minesweeping systems.

Such relics are still scattered across the Aegean islands, such as in Irakleia island (Battlefield Archaeology: Destroying WW2 sea mines in the Aegean Sea)  


Another one is located on a… rooftop in the village of Marmara in Paros island, Greece, with no details as to how it ended up there, certainly though it manages to catch the eye of tourists who happen to pass by.


The “Oropesa Sweep” was developed by the Minesweeper Oropesa in 1919.It was used to clear mines laid in World War one(1914-1918).
The system was used in the North Sea and English Channel as well as in coastal waters all over Europe.

The system was improved by the introduction of the Multi-Planed Otter and better quality steel sprung cutters.


The system consisted of:

A cable,to tow the equipment.
A “kite” to control the fixed depth of the sweep.
Cutters connected to the Cable to cut the mine mooring cable.
An “otter” to pull the cable and cutters outwards and away from the ship.
And Oropesa Float to stop it all sinking to the bottom.


The 1st minesweeper (with twin oropesa system) was often preceded by a shallow draught motor boat with a small twin Oropesa system.
This was to reduce the risk of contact with a mine for the 1st minesweeper.

A view of the amidships section of the ocean minesweeper USS ENGAGE (MSO-433) showing a paravane in its storage rack.
A view of the amidships section of the ocean minesweeper USS ENGAGE (MSO-433) showing an oropesa (paravane) floating device in its storage rack.

The other minesweepers followed in the channel cleared by the 1st minesweeper, The last two would drop Dan-Buoys aft to mark the swept area.

An oropesa found in the UK
An oropesa floating device found in the UK

This would leave a safety margin of one sweep either side.

The Mine mooring cable slid along the towing cable until it came in contact with the cutters this would cut the mine mooring cable and the mine would float to the surface.
Then it was destroyed by rifle fire.