The picture above shows the Senate House, wth an Austin van parked on top. This really happened, in 1958. The Caius college site has a full description of the plot, penned by one of the purpetrators, which is very well written.
The Cambridge graduation ceremony is so silly it deserves a decent description, which is elsewhere.
For you architecture and history junkies, here's some of the Senate
House's vital statistics. It was built between 1722 and 1730 of Portland
stone, under the direction of the architect James Gibbs of Aberdeen.
The style of the exterior is a cross between Wren, Palladian revival, baroque
(Pietro Cortona) and French. Inside is one large room with wooden
galleries on three sides. The galleries were fitted between 1725
and 1730 by James Essex the Elder. The rococo plastered ceiling is
the work of the Italians Artari and Bagutti. The cast iron railings
around the Senate House were made in 1730 and so were among the earliest
in Cambridge. Originally it was intended to form one side of a three-sided
court, but as happened during the construction of Downing
College, the money ran out, so the Senate House was the only part built.