Country to Capital from GoBeyond, I've done the London 50k twice - good race but I'm not sure if Rory is doing any next year, he's confirmed the Cardiff 50 is not going ahead, and that's his home town ultra...
Sounds like you have your eyes open! It was a bit of a culture shock to me - I was used to well groomed trails and 'undulating terrain' 2 years ago!
This is my Garmin track from 2011 they changed the course a bit in 2012 and added some extra miles and ascent for more UTMB points. Haven't looked at the course this year - but I presume it's back to the 2011 version.
Bits to watch out for!
The climb up to Tor y Foel is very steep and muddy
There's a notoriously boggy section once you've gone over Pontsticill reservoir and CP2, (miles 15-20). Last year it was frozen solid, but the other 4/5 times I've done it it's been knee-depp in bogs!
The descent off Pen y Fan is one of the best descents I've ever done - so much fun
I guess this is the MCN Brecon Ultra? I've done it twice and am doing it again as the final one in the 2013 Welsh One Day Ultra Series...
They are brilliant, friendly events - I don't know what your background is, but here's a bit of a wake-up call jus in case
It's TOUGH, hilly, muddy, boggy - some sections will have you crawling on hands and knees. My 40-mile PB time is 6:15, on this course it's over 9 hours! You'll start and finish in the dark.
DON'T skimp on kit, take warm, waterproof clothing - the weather changes rapidly up in the mountains. In May, a glorious, warm morning turned into a freezing cold battle on the ridge up to Corn Du and Pen y Fan.
What caught me out on the first year was the hills and terrain, (muddy, boddy, rocky) if you can get some hours in trudging up and down big hills then that's the best advice I can give really.
Having said that, it's an amazing course - not as challenging as the summer version, (you don't go up Cribyn). There's a great crowd who do these events regularly and the organisers are just some of the nicest people you'll ever meet. My profile photo was taken at last year's event halfway up to Pen y Fan!