In pictures: Ai Weiwei's journey from Beijing to London

The Chinese artist and activist has been allowed to leave his home country for the first time in four years. Here, he exclusively shares his Instagram pics documenting his momentous trip from Beijing to London, via Munich, for the opening of his retrospective at the Royal Academy.

July 22

Ai Weiwei is reunited with his passport having been banned from leaving China for over four years. It was confiscated by officials at Beijing airport in April 2011, as part of wider crackdown on activists in the country.

July 25

A tender moment on Skype as the artist tells his son Ai Lao, who lives in Germany, that he's received his passport and can travel abroad again.

July 29

At the gates of the US Embassy in Beijing. Having got his passport back, Ai can apply for a visa. 

July 30

Ai Weiwei's passport with his UK visa, with a duration of 20 days. The visa has since been extended to six months after an intervention by the Home Secretary.

July 30

With Ai Lao and partner Wang Fen after arriving at Munich airport.

July 31

Swimming in the hotel pool of Bayerischer Hof in Munich after being reunited with his son. The six-year-old and his mother have been living in the Germany for the past year, after Ai asked them to leave China.

August 2

By the Isar river in Munich - with an interesting choice of words made of stones from the bank.

August 3

The results of a brain scan in Munich. Ai was beaten by a policeman in Beijing in 2009 and had emergency surgery for a haemorrhage the same year.

August 15

Ai Weiwei with artist and Pussy Riot member Nadya Tolokonnikova. A fellow activist, she's also no stranger to clashing with her home country's government.

September 6

The plane from Germany to London: Ai Weiwei arrives in the capital for his show at the Royal Academy. Work on display will include an 80-tonne installation of steel rods salvaged from the wreckage of the 2008 Sichuan earthquake.

Read our review of Ai Weiwei's new show.

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