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 being built in the 1920s by the Belgian colonial government as a home for civil servants and Swahili traders. This latter group were mostly members of the Islamic faith, which led to Nyamirambo being known as the "Muslim Quarter". Nyamirambo's Green Mosque ("Masjid al-Fatah") is the oldest mosque in Kigali, dating back to the 1930s. Travel publisher Rough Guides has described Nyamirambo as "Kigali's coolest neighbourhood", citing its multi-cultural status and an active nightlife, which is not found in much of the rest of the city. North of Nyamirambo, and west of the CBD is Nyabugogo. Situated at the lowest