This is the second time I've run this 10k. A different route this year which I thought better represented Cardiff (past the castle twice and up through the the fields beyond). I can see from other reviews that some people had a nightmare registering on the day (this may have been the cause of the 15 min delayed start), however I got there early and had no problems at all. The route is pretty flat. It got a bit bottle necked towards the start, but soon spread out pretty well. It was well marshalled and there was a decent crowd (less than last year, possibly because a Tour De France winning Geraint Thomas and Chris Froome were riding the Welsh stage of the Tour of Britian just up the road!) Good water points (although the bottles were way too big, what a waste!). The Cardiff 10k is a bit of an institution, has a great atmosphere and I will always run it. It's also a good warm up for Half Marathon a few weeks later.