Listed Building record MDO6588 - Mulberry Harbour off Castletown Pier, Portland Harbour

The southernmost of two Phoenix units of a World War II floating harbour which were produced to assist in the Normandy Invasion of 1944. Two 'Phoenix' units of a World War II floating harbour which were produced to assist in the D-Day landings and Normandy invasion of 1944. Constructed of reinforced concrete, eight of these units were located in Portland Harbour in 1946 to provide protection for the construction of a new pier, of which two now remain, permanently moored, and lying due north-south, about 115 metres north of Castletown Pier.

Two Phoenix units of a World War II floating harbour which were produced to assist in the Normandy Invasion of 1944. Constructed from reinforced concrete, eight of these units were located in Portland Harbour in 1946 to provide protection for the construction of a new pier; two of these now remain, permanently moored, and lying due north- south, about 115 metres north of Castletown Pier. Each unit is circa 60 metres long by 18 metres wide, and 15 metres high. Most of the floating Harbour, or Mulberries as they were code-named, was towed across the English Channel to serve the D-day landings on 6th June 1944 on the Normandy beaches; these two sections are approximately sited in Portland harbour as a reminder of this remarkable enterprise. <1-2>

The Second World War Phoenix caisson unit described above is visible on aerial photographs of 2008 and 2009 to the north of Castletown, Portland. <4-5> This site was digitally plotted during the South West Rapid Coastal Zone Assessment Survey (Dorset).

<1> Historic England, Historic England Archive, BF108055 (Index). SDO14738.

MULBERRY HARBOUR, HM NAVAL BASE, PORTLAND

<2> DOE (HRR), 17 May 1993, List of Buildings of Special Architectural or Historic Interest: Borough of Weymouth and Portland amendment 1993 (Scheduling record). SWX2185.

<3> Le Pard, G, 1995-2003, Dorset Coast Forum Maritime Archaeological Database, Structures 1 (Digital archive). SWX8707.

<4> Channel Coastal Observatory, 20-JUL-2008, CCO Aerial Photographic Coverage 2008 (Aerial Photograph). SDO12674.

<5> XX-XXX-2009, Google Earth (Aerial Photograph). SDO12705.

<6> National Record of the Historic Environment (Digital archive). SDO14739.

Record last edited

Jul 26 2023 10:24AM