It may feel like summer arrived weeks ago: deckchairs are already out in parks, holidays are booked, barbecues have been fired up and – in true British fashion – we've no idea what to wear to our air-conditioned offices.
But technically speaking astronomical summer didn't begin until today, when Britain enjoys the longest day of 2018.
Read on below to find everything you need to know about summer, the solstice, traditions, the significance of Stonehenge – and how to celebrate it.
When is the longest day of the year?
In the northern hemisphere, summer solstice, or longest day of the year, takes place between June 20 and 22 each year.
This year it falls today - Thursday, June 21 - when the UK...