The objective of the cruise was to download data from the sea-bottom distancemeter stations in the Kumburgaz Basin, Marmara Sea. The stations were installed by the Marine Geosciences Laboratory in Brest and Geomar Institute in Khiel during RV Pourquoi Pas ? Marsite cruise late October 2014. The first data set was downloaded during the 3rd leg of the Marsite cruise, after only 15 days of operations. A 2nd cruise was organized in April 2015 by GEOMAR using RV Poseidon (POS484) to collect the data after 6 months of operation. A 3rd download was performed in April 2016 using again RV Poseidon (POS497). This cruise was the 4th data collection and was organized by the Technical University of Istanbul (ITU) using RV Yunus. The stations have been ranging on the sea-bottom for 2 years and 4 months. The RV Yunus was on site the 4th of May 2017 from 13h15 to 20h30 (local time). After a night in Mimar Sinan, the ship was back on site the 5th of May from 8h00 à 13h30 (local time) and returned back to Istanbul late afternoon. In total, 12h45 of effective work were spent on site (about 30 nautical miles from Istanbul). The conditions were optimal with a beautiful weather and a calm sea.