Mongomo

Mongomo sits deep in the rainforest near the Gabon border and owes its rather unusual scale to being the home town of the presidential family, which has left it with a basilica far larger than a town this size would otherwise ever warrant. The building dominates everything else in the town and is really the one reason travellers passing through stop at all. Political sensitivity around that particular family connection is genuinely worth being aware of before asking too many questions locally. The one border crossing nearby serves regional trade rather than anything like tourism.