Switzerland tunnel: The oddest moments of the opening ceremony Published duration 1 June 2016

image copyright AP image caption We're not sure what this was all about either

From the World Cup to the Olympics, it is not a significant event if you don't have an unusual opening ceremony to go with it.

This was also the case when the Gotthard base tunnel, the longest and deepest in the world, was inaugurated on Wednesday.

Here are some of the most striking moments from the ceremony - we have tried to explain what is going on as far as possible. It was not always possible.

Warning: This article contains partial nudity

image copyright AP image caption The ceremony represented different aspects of Swiss culture - at this point, milk floats drove in a procession

image copyright AP image caption In the middle of all of this, an actor sat down, looked rather underwhelmed by everything, and ate his lunch

image copyright AFP/Getty Images image caption A topless woman decked as a bird hovered above actors representing the nine construction workers who died during the building of the tunnel

image copyright AFP/Getty Images image caption It is unclear what the German, French and Italian leaders, who were all present, made of the ceremony

image copyright EPA image caption Parts of the show proved very popular with some of those in the audience, however

image copyright Twitter/@journodave image caption Some viewers were left baffled, as, perhaps, were some participants

image copyright EPA image caption At one point, there were lots of people rolling around in white underwear

image copyright EPA image caption They, too, looked a bit blank about the whole thing - it was put together by German director Volker Hesse, whose most famous work has been done in Switzerland

image copyright EPA image caption The ibex, that is native to the Alps, played a prominent part in the ceremony

image copyright Twitter/@FPeressinotto image caption One Twitter user wrote: "We're opening a tunnel, and here are two people dressed as ibex pretending to have sex"

image copyright EPA image caption More than 600 actors reportedly took part in the ceremony - an experience they are unlikely to forget any time soon