The Dover Strait is the world’s busiest shipping lane. 500-600 ships a day pass through the narrow strait between the UK and France. Cargoes include oil from the Middle-East to European ports, and various commodities from North and South America to European customers. In 1999, 1.4 billion tonnes gross, carried by 62,500 vessels passed through the Dover Strait.
The Malacca Straits, off the Malaysian peninsula, is believed to handle more traffic (vessels), but less tonnage. Figures from other areas of the globe (i.e. Malacca, Gibraltar, Bosphorus etc.) are a little hard to come by as the UK Coastguard maintains a strict record of traffic, which is not always the case in other countries.