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, being built in the 1920s by the Belgian colonial government as a home for civil servants and Swahili traders. The 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 to the 1930s. Travel publisher Rough Guides described Nyamirambo in 2015 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 part of the city, in the valley of the eponymous Nyabugogo River, Nyabugogo is home to Kigali's principal bus and share taxi station, with vehicles departing for numerous domestic and international destinations.