See the three landmarks of the Golden Circle and ride a snowmobile across Langjökull, Iceland's second-largest glacier — all in a single guided day from Reykjavík. Reykjavik Excursions has run Iceland's classic day tours since 1968, so you travel in a comfortable, carbon-neutral coach with an experienced guide and leave the driving, the route and the weather to people who know them. The Golden Circle begins at Þingvellir National Park, a UNESCO World Heritage Site where the North American and Eurasian tectonic plates visibly drift apart, and where Iceland's parliament was founded in 930 AD. The route continues to Gullfoss, the thundering two-tier waterfall, and the Geysir geothermal area, home to Strokkur — the reliably erupting hot spring that gave every other geyser in the world its name. After the sightseeing, the tour climbs into the highlands for the part you'll remember longest: an hour on a snowmobile across the vast white expanse of Langjökull. Full protective gear and a safety briefing are provided at the glacier base, so first-timers are looked after from the moment they step off the coach.