The UK has a strong festival culture, ranging from enormous music events to centuries-old traditions.
Glastonbury Festival (June, Somerset) is the world's largest greenfield music festival, held most years on a farm near Pilton. Beyond the five main stages, there are theatre, circus, poetry, healing fields and an extraordinary range of performers across hundreds of smaller venues. Tickets sell out within hours and are allocated by ballot. If you want to go, register well in advance.
Edinburgh Festival Fringe (August, Edinburgh) is the world's largest performing arts festival, with thousands of shows across more than 300 venues in the space of three weeks. Comedy is the dominant form, but there's also theatre, dance, physical performance, opera and cabaret. Many shows are free or cheap. The Fringe runs alongside the Edinburgh International Festival, the Edinburgh Art Festival and others — together they make August in Edinburgh one of the great cultural events on the planet.
Notting Hill Carnival (August bank holiday weekend, London) is Europe's largest street festival, drawing up to 2 million people over two days. Founded in the 1960s by London's Caribbean community, it fills the streets of west London with sound systems, steel bands, elaborate costumed parades, and Caribbean food stalls. Sunday is traditionally for families; Monday is the main parade day.
Hogmanay (31 December–1 January, Edinburgh and across Scotland) is Scotland's New Year celebration, with street parties, ceilidh dancing and the tradition of first-footing. Edinburgh's street party is one of the largest ticketed New Year's Eve events in the world.
Guy Fawkes Night (5 November) marks the failed Gunpowder Plot of 1605 with bonfires and fireworks displays across the country. Local councils and organised events are the best way to see it; improvised fireworks on the street are a different experience.
The Chelsea Flower Show (May, London) is the world's most prestigious horticultural show, run by the Royal Horticultural Society. Tickets sell out quickly.
Cooper's Hill Cheese Rolling (late May, Gloucestershire) is exactly what it sounds like: a wheel of Double Gloucester cheese is rolled down a steep hill and participants chase it. It started as a local tradition and is now a spectacularly chaotic event that draws crowds from around the world.