If most of the battles are located in wide open desert spaces, the real issues are harbors and oasis.
There are few sea ports on the Libyan coast. Actually, there is only one which is important between Bengazi and Alexandria : Tobruk. The ressuplying is coming on boats. Both sides realized that once away from their harbors, the ressuplyong is becoming too hard and stop them from giving the finishing blow. Moreover, Tobruk has a factory that is producing 180 000 liters of distilled water a day.

The English troops are capturing Tobruk’s harbor from the Italian troops in 1940 and fortify it. Bunkers, anti-tank ditch, minefields, two Australians divisions and some armoured elements are the defences of the town.
The German troops are surrounding Tobruk and besieged it in april 1941. They stay 8 months but all the attacks are failing. The garrison is frequently ressuplied, the wounded soldiers are evacuated (that are coming from Poland, New Zealand, and some English relief troops are coming in aout). In the end, the “crusader” operation eventually breaks the besiege with hundreds of destroyed tanks in december 1941. The victory was hard to obtain. Rommel is complaining about the lack of readiness to fight from the Italians troops (one English officer has captured, alone, 70 italians officers that were having a lunch in the Jalo oasis). Tobruk will stay in the control of the British troops.

An oasis can be compared to a port, as the desert is sea of sand. The oasis is the only place where camp can be installed because of its water resources. There is a battle in each oasis. The most famous one for the French is the Bir Hakeim battle.
It is an oasis located in the far south of the desert. When Rommel arrives in El Alamein in mai 1942, he attacks the English troops that were preparing for the attack. The defence line is broken, and the allies are weakening. The German troops are trying to surround them to definitely destroy the VIIIth army. But an obstacle stops them : the oasis of Bir Hakeim, transformed in a fortified camp by the 1st Free French Brigade of the General Koenig. The brigade is defending even though the water and the ammunition is limited. In the same time, the VIIIth army is falling back and avoid annihilation. 2200 (on 3500) French troops manage to escape by themselves.

But this time, Tobruk has been captured and Rommel lays his hand on the huge harbor’s stocks of water, and more important, of gas. But Tobruk is not the break so much expected by the troops, because the English troops are attacking the ressuplying boats from the Malta Island. The capture of Tobruk is just a few days grace before stifling.