In pictures: Prince George's first year

Prince George celebrates his first birthday on Tuesday. It has been a busy 12 months since the third in line to the throne was first introduced to the world on the steps of a London hospital.

Prince George was first unveiled to the world outside St Mary's Hospital in London by his father and mother, the Duke and Duchess of Cambridge, in July last year.

Hundreds of journalists and well-wishers gathered outside the hospital to catch a glimpse of the future king.

The prince was christened in October at St James's Palace in London. He was baptised by the Archbishop of Canterbury and wore a replica of the lace and satin christening gown made for Queen Victoria's eldest daughter, Victoria, the Princess Royal, in 1841.

The young royal's first official tour came in April 2014 when he accompanied his parents to New Zealand and Australia. This picture, taken at Wellington Military Terminal, marked only the third time he had been shown off in public.

Prince George appeared on a number of occasions during the trip, such as when he played with a toy at Government House in Wellington.

He proved a popular attraction down under and was given a number of gifts by people he met.

Prince George did not feature at all public events, spending time with his nanny while the Duke and Duchess of Cambridge were on official engagements. On the Australian leg of the tour, one of his appearances was at Taronga Zoo in Sydney, where he was presented with a toy bilby.

The Duke and Duchess said they were "bowled over" by the support the family received on the trip.

In June, Prince George was photographed walking with the help of his mother at Cirencester Park Polo Club - the first time he had been seen on two feet in public.

And in the first of three official pictures released to mark his first birthday, he is seen walking unaided at London's Natural History Museum.

Another image from the set shows Prince George reaching out to touch a butterfly, which has landed on his father's hand.

And the final birthday picture shows the family staring into the sky, Prince George with his hand outstretched like any other curious youngster.