The London Symphony Orchestra will set up shop in Trafalgar Square for the fourth year running to treat vast crowds of classical music fans to a free performance. The schedule for 2015 is all Shostakovich, with Scottish violinist Nicola Benedetti playing his Violin Concerto No 1. Large screens either side of the stage will ensure everybody in the square can see, but not even the thickest jumper will save your bum from going numb on that concrete: bring a cushion.
(BMW LSO Open Air Classics: in previous years an estimated 10,000 people enjoyed the free concert, so arrive early to get a good spot. No glass or furniture is allowed in the square.)