Great North Run is taking place in Newcastle on the same day.
There is likely to be a lot of traffic on the A1 and A19 north bound early morning and south bound late afternoon.
Registration for all Viking Chase races will close at 10:30 am prior to a briefing at 10:35 am. See Cleveland Search & Rescue website for details.
This link http://www.annes-mountain.co.uk/Lordstone.htm has pictures of the hillside used for Viking Chase. The second one in particular gives a good idea, although it is steeper. The older age groups U16 and U18 (maybe U14 - sorry can't remember) drop over the horizon and descend a long way down, probably below the start/finish. There is also a picture that looks back down to the start. A mixture of stone path, sheep trod and grass, plus fantastic views.