Geothermal pools, Þingvellir's continental rifting, Strokkur erupting on a five-minute clock. Day-one Golden Circle drive with the rented 4WD: Þingvellir National Park, Geysir, Gullfoss waterfall. Evening at Blue Lagoon (Retreat Spa for the upgrade with the in-water bar). Day two: Reykjavik bar crawl on Laugavegur (80+ venues in a half-mile), dinner at Grillmarkaðurinn (grilled Atlantic catfish, lava-grilled lamb). Day three is Sky Lagoon's seven-step ritual or a glacier helicopter charter. Keflavík (KEF) is 45 minutes; the Flybus shuttles in for $35/person.
Five quick questions, then we build the full itinerary — lodging, daily schedule, dining, bars, the group-chat message — and drop you into a Trip Room you can share with the crew.