Seria is not a tourist town and makes no apology for it — it is an oil town, and the oil industry is the reason to come. The beach is modest, the streets are quiet, and the main sights are monuments to petroleum. But for travellers curious about how Brunei's extraordinary wealth was actually made, Seria rewards a half-day stop: the Oil and Gas Discovery Centre is genuinely well done, the Billionth Barrel Monument carries real historical weight, and the sight of nodding-donkey pump jacks scattered across the coastline is unlike anything else in Southeast Asia.