Red Castle Revisited – The Survey Ship ECHO has become the first Royal Navy vessel to return to Libya since the fall of the Gaddafi regime last autumn (2011).   The “Red Castle” is the historic fortress Assaraya Alhamra (the Red Castle), the bastion of the port of Tripoli.   The survey ship spent five days in Tripoli as part of initial steps to rebuild the republic’s Navy after most of Colonel Gaddafi’s fleet was knocked out in the conflict.     Using the multi-beam echo sounder fitted on the ECHO they also discovered an uncharted wreck and with the side scan sonar in the water to fully investigate the discovery one suspected sunken WW2 liberty ship was discovered.