The route is all grass and very flat, just 30m height change per 5km lap, though to be honest I am not sure where those 30m are, it could just GPS trickery.
The route is nice and compact enabling you to see runners at different parts of the course as you go. There is also plenty of space for easy overtaking.
The 5km is a single lap course, the 10km route is two laps bringing you back through the start/finish area to get a cheer from the waiting runners as you start your second lap.
The route is largely flat, with a good mix of grass and trails. There are great views over the Bristol Skyline and a pass by a ghostly sculpture garden. The course is marked with reflective signs and glow sticks at regular intervals making it very easy to navigate.