October 2nd, 1925: four covered-top double-deckers debut on the Elephant to Epping route, drawing queues of curious Londoners. A century later, their descendants — 8,800 buses, 6,000 of them double-deckers — knit the capital together with 5 million journeys a day and 300 million miles a year. From four pioneers at the Elephant to a red fleet that could lap the Earth 12,000 times or reach the Sun in four months — London’s buses aren’t just transport. They’re a solar-system-sized lifeline, a cosmic commute.