The first woman home this year was Jenny Horne, of Aberystwyth, in 2hr 46min 41sec.
The race winner received a cup and 1000 guineas.
The marathon, staged around Powys countryside, saw 300 solo runners and 50 horse-and-rider combinations take part. There were also 111 relay teams of three members each, in what was the 31st running of the event at Llanwrtyd Wells.
Horses have dominated the event, with men winning it only twice in its history - the first time in 2004 when Huw Lobb claimed victory by two minutes. That win netted Lobb a special prize fund of £25,000.
A man also claimed victory in 2007.
The course is steep and the terrain varied to make the contest as even as possible. Competitors race across farm tracks, footpaths, forestry roads and open moorland, with several short stretches over tarmac.
It is very hilly, with a total ascent of 3000ft.
Rain had made the ground even softer and the going tougher than usual.
Horses are vetted before the race and afterwards, with a midway check also mandatory.
The race began in June 1980 after a chat over a pint in the Neuadd Arms Hotel.
The then Landlord, Gordon Green overheard two men discussing the relative merits of men and horses.
The enterprising Gordon, never one to miss an opportunity to promote Llanwrtyd Wells and improve business at his hotel, decided to put it to the test.
And so began Green Events and its first, longest standing and now internationally acclaimed event.
The course was changed in 1982 to provide a more even match between the man and the horse resulting year on year in very close finishes - sometimes with the horse winning by only a few seconds.