Lubumbashi in 3 days: the DRC copper city that produces 70% of the world's cobalt (every electric vehicle battery runs on Katanga), where Gustave Eiffel's Belgian engineers built a 1,344km railway to the Atlantic, where 155 Irish UN peacekeepers held off 6,000 Katangese soldiers for 5 days in 1961, and where Congolese rumba music developed in the mine compound cultural programmes designed to prevent workers from organising.