Off road/trail Marathon

I'm looking at doing my 1st Trail/Off road marathon this year, I do half my training miles crossing bogs, trails, tow paths, rivers, moors etc, i love running off road and getting muddy, dont worry about times and just enjoy changing terrain etc. But all my serious races (apart from the fun spartan races/tough mudder) are road running, which i do enjoy but I fancy a new challenge, 

Anyone done any of these? race reports/reccomendations would be most helpful,

thanks guys n gals. 

I;m planning on doing the South Downs Marathon in June. Not done it before so can;t recomend it persoanlly but everything I've read bout precious editions has been positive.

you can't go much better than this:

highland fling

Beachy Head Marathon is 95% off road - very highly rated every year.

http://www.visiteastbourne.com/events/BeachyHeadMarathon.aspx

I love doing off road events, they are great fun. Did the endurance life Dorset 10k in December and that was really good and i thought well done, so would recommend any of their events, i'm going to try the half next time!
However there are a lot of lower profile events that are just as challenging. I entered the Avebury 8 last year, quite local clubby but real cheap, no frills and loads and loads of mud. just search for trail races in the event finder on this website

This is supposed to be a good'un!

http://www.trionium.com/greensand/

i'm in the midlands Andy but i can travel anywhere in europe if its worth it. 

thanks for the suggestions, it doesnt have to be 26.2 no, but i'm not sure im ready for a 50 miler,gonna look at the beachy head one a little more, sounds ideal, and the white peak one too, love hills. still open to ideas

The Endurancelife events are excellent, locations, atmosphere a but lack of personnel is usually apparent. Would still give them 9/10 ! One of the best events I have done is the Salisbury 5-4-3-2-1 event. Choice of 10k to Ultra distance. The name means five hills, four rivers, three country estates, two castles and one cathedral on the route. Organisation is 10/10. This year it is 11th of August so the weather adds a bit of an extra challenge. The event is in aid of the Firefighters charity

The Atlantic Coast Challenge, organized by VoTwo and held every autumn (this year in early October) is a good one. Three days along the Cornish coastal path from Padstow to Land's End. You can do single days. Day 3 is particularly, erm, challenging. Lots of swamp and ups and downs.

I'd imagine their other challenge series events are similar. I did the ACC in 2010 and it was good fun.

+1 for Beachy Head.

EDIT... I typed those arrow thingies to point at me on the left running up a slippery chalky path in the Beachy Head marathon, but it didn't like it. 

Lakeland Trails - they do a marathon and other shorter events through the year. I did the first marthon and can reccomend it, although it is hard since it's up and down mountains with limited support (there's a review on the events forum if you search for it). I also did Staveley with the same company so can say in my experience they are good organisers of quite relaxed events (no big city formality).

Look at Endurancelife website, all coastal trail series stages have marathon distances.

I ran the South Downs a couple of years ago. It's challenging and also beautiful. Salomon also sponsors the Kielder Marathon, which calls itself 'Britain's most beautiful marathon' and I believe is slightly less challenging than the South Downs. I'm considering running it this year.

Rivington Trail (near Bolton) half or full mara in October run by 2:09 events was fun last year. Hilly, muddy, and generally good fun.

Lakeland Trails - They do a number of events throughout the year, all around 15k & also a Half & full Marathon in July I think.

Doing Trail Marathon Wales this year on June 22nd, will be my first off road marathon.

Yorkshireman is another I think.

great list guys, thanks a lot, made notes to check out all of them.