documenta 14, which has just started in the city of Kassel and will run until September 17, takes place once every five years in this otherwise unappealing city in the midriff of Germany – although the big difference this year is that it kicked off with a pre-show in Athens, and that artists are meant to have worked with both destinations.

The first documenta, back in 1955, was originally planned by local art professor Arnold Bode. At the time, Kassel was still reeling from the impact of war. As a centre for a lot of heavy industry – tanks, locomotives, etc – it had been around 85 percent destroyed in Allied bombing raids, and it was hastily rebuilt in 1950s style.

Bode’s initial idea was to display art from movements that had been labelled as ‘degenerate’ by the Nazi regime, such as Fauvism, Expressionism, Cubism, Blauer Reiter and Futurism. Over the years, however, the focus has shifted to any contemporary art, coming from all corners of the world. This year there will inevitably be a strong Greek bias, such as the giant ‘Parthenon of Books’ in the Friedrichsplatz.

documenta’s approach is to hire a completely artistic director every time, so that the show remains fresh and original. And this year’s director, Polish art critic Adam Szymczyk, has selected around 160 artists, most of whom will regard being accepted by the exhibition as an almighty step forward in their careers. Artists generally have to come along with their own funding, but there’s also very generous outside sponsorship if their cash supply runs a bit short.

In Kassel, the show has a couple of key venues, the Fridericianum and the Gloria Cinema, but there will be art works all over town, in parks, on top of buildings, on street corners, and even under the ground.