Another event in Assen yesterday was the Winter Triathlon.
There were about a thousand competitors, either as individuals or in teams for a "relay". Most people took part in a 10 km run, a 50 km cycle ride and 20 km on ice skates, but there were also sprint events where the distances were halved. Ages ranged from 20s to 70s.
I'm a hopeless runner and can't skate, so triathlon isn't really my thing, but I went to watch for a bit.
The cycling and running events involved the police being out in force closing roads.
It seems relatively easy to get road closures here compared with back in the UK.