Kigali Rwanda's highest buildings, including the 20-storey Kigali City Tower, are located in the CBD, as are the headquarters of the country's largest banks and businesses. Other buildings in the CBD include the upmarket Serena, Marriott and Mille Collines hotels, the University Teaching Hospital of Kigali, the national university's College of Science and Technology, and government buildings such as the National Bank of Rwanda and the Ministry of Finance and Economic Planning. To the south west of the CBD, and also on the Nyarugenge Hill, is the suburb of Nyamirambo. This was the second part of the city to be settled,
Kigali part of the upper headwaters of the Nile, forms the western and southern borders of the administrative city of Kigali, although this river lies somewhat outside the built-up urban area. The largest river running through the city is the Nyabugogo River, which flows south from Lake Muhazi before flowing west between Mount Kigali and Mount Jali, and draining into the Nyabarongo. The Nyabugogo is fed by various smaller streams throughout the city, and its drainage basin contains most of Kigali's territory, other than areas in the south which outflow directly to the Nyabarongo. The rivers are flanked by wetlands, which