Vince - this sounds tough but fabulous, I just wish I could ever be fit enough to run it! In a similar vein (tough, cross country style) there is also the very beautiful Ashridge Boundary Run the week before Orion, this one is about 16.5 miles. A few of us have run this and would recommend it if you want a challenging off road run through beautiful scenery. I've run it in sunshine, rain and snow and it doesn't get any easier!
Hey Vince, I’m going to run this.... haven’t done the exact route before however have run the Mercury 10 miler which is a shorter version also hosted by Orion on the 08th February and it’s a great course with some big hills, think Orion midweek league only more hills and off road 😊. Wouldn’t recommend spikes for this definitely trail shoes.