Five days is widely considered a "perfect introductory stay" for London, allowing you to see the major landmarks without feeling completely overwhelmed. A typical 5-day itinerary would cover the "Big Three" (Westminster Abbey, Big Ben, and the Tower of London), a day for world-class museums like the British Museum or the V&A, and a trip to the West End for a musical. You would also have time for a scenic Thames River cruise and a stroll through the South Bank. However, London is massive and historic; 5 days won't allow for extensive day trips to places like Stonehenge or Bath without sacrificing city time. In 2026, with the efficiency of the Elizabeth Line and the underground, you can move quickly, but you'll still only scratch the surface of London's diverse neighborhoods like Shoreditch or Richmond. It is enough to fall in love with the city, but you'll likely leave feeling like there is much more to see on a return visit.