|Unit||2/4th Australian Infantry Battalion|
Derna, a coastal town in the Libyan region of Cyrenaica, was the site of the third major action fought by Australian troops during the Second World War. Derna lies at the mouth of a large wadi that stretches inland for almost twenty kilometres and is in places over 1.5 kilometres wide and over 200 metres deep. As the 6th Australian and 7th British Armoured divisions advanced after their victory at Tobruk, a rearguard from the 10th Bersaglieri Regiment occupied positions around Derna to allow the retreat of Italian forces towards Benghazi. The 2/11th Battalion first made contact with the rearguard at the Derna airfield on 25 July. On the east bank of the wadi, and at the edge of the coastal escarpment, the flat, open terrain around the airfield made progress difficult against particularly determined resistance. Further to the south, the 2/4th Battalion advanced to the wadi and that night crossed it and established a foothold on the west bank. The next day orders were given for the 2/11th to push beyond the airfield towards where the road wound down the escarpment to Derna, while the 2/8th Battalion crossed the wadi between the 2/11th and the 2/4th and advanced towards the town along its north bank. Over the next two days the 2/11th made steady, but extremely slow progress, but the 2/4th was unable to move forward of the western bank of the wadi, which led to the 2/8th's advance being cancelled. The advance of other British Commonwealth units further to the south of the Wadi Derna eventually threatened the rearguard with encirclement and it withdrew on the night of 28 January. Derna was entered, without opposition, by a patrol from the 2/11th Battalion on the morning of 29 January. Precise casualty figures for the battle for Derna have not been compiled but at least 15 Australians were killed.