Smile for the Camra: 'Hat day' at the British Beer Festival

Image source, Yui Mok/PA Wire

Image caption, Fancy headbeer - some amoosing and some on fire - was on display across London's Olympia Exhibition Centre

The Campaign for Real Ale (Camra) has held its annual "hat day" at the Great British Beer Festival.

Visitors are asked to wear their "silliest and craziest drinking hat" at the halfway point of the five-day festival.

Image source, Yui Mok/PA Wire

Image caption, Put your drinking cap on to find some good pubs nearby

Image source, Yui Mok/PA Wire

Image caption, Yeaster bonnets: Hats were decorated with beer mats, bottle tops and all sorts of other ale-related paraphernalia

An estimated 50,000 people will have the chance to sample more than 1,000 different beers, ciders, perries, wines and gins throughout the festival.

Image source, Yui Mok/PA Wire

Image caption, Tipple of the hat to Nicky Manix who shows off her homemade Great British Beer Festival (GBBF) hat

Image source, Yui Mok/PA Wire

Image caption, Do you like your beer with a head?

Siren Brewery based in Berkshire won the prestigious Champion Beer of Britain.

Its Broken Dream Breakfast Stout was described as having a "deep and complex blend of chocolate, coffee and a touch of smoke" by the festival's judges.

Image source, Yui Mok/PA Wire

Image caption, Beer in your bonnet? This visitor also showed off his homemade creation

The beer festival - at London's Olympia Exhibition Centre - runs until 11 August.