Siege of Khartoum support of the Mahdi, and cut the Egyptian traffic on the Nile and the telegraph to Cairo. Communications were not entirely cut, as runners could still get through, but the siege had begun and Khartoum could only rely on its own food stores, which could last five or six months. On 16 March an abortive sortie from Khartoum was launched, which led to the death of 200 Egyptian troops as the combined forces besieging Khartoum grew to over 30,000 men. Through the months of April, May, June, and July, Gordon and the garrison dealt with being cut off as food
Khartoum Bridge (finished in October 2007) and the Tuti Bridge that links Khartoum to Tuti Island. In the 21st century, Khartoum developed based on Sudan's oil wealth (although the independence of South Sudan in 2011 affected the economy of Sudan negatively). The center of the city has tree-lined streets. Khartoum has the highest concentration of economic activity in the country. This has changed as major economic developments take place in other parts of the country, like oil exploration in the South, the Giad Industrial Complex in Al Jazirah state and White Nile Sugar Project in Central Sudan, and the Merowe Dam