2006.10.29 - 2006.11.04 four Lithuanian cavers, lead by Henrikas Ramonas, took part in the expedition to the cave Optimistitcheskaya (west Ukraine). The expedition was organized by Lvov's caving club "Cyklop" and consisted of 16 participants in total (besides the Lithuanians, there were 11 Ukrainians and 1 Belorus).