Machen Trail Races
Half marathon and marathon Run through the beautiful Rudry Common, Cefn Onn Country Park, Coed Craig Ruperra and, for the marathoners, the top of Machen.
Date: 28 November 2026
The race has everything! For those training for mountain ultras to those looking for a lovely winters day in the woods, this is the race for you. For the half marathon, there are wooded single tracks, open moors and pretty streams. The marathon adds a mountain feel with the exposure of Machen mountain, yet without the risks of a mountain race in winter.
A race that many return to, because the route is just 'special'.
Half Marathon Route
The half marathon starts in Machen, with the route winding its way through some beautiful single track trails to Rudry Common. Once over the common, you'll run into Caerphilly Forest, over the hill and a glorious downhill belt to the Cefn Onn checkpoint. A long climb takes you back to the top of the ridgeway passing the Lisvane / Llysfaen trig point. You'll hit the woodlands next which will leads you to Ruperra Castle before heading down into Draethen (where sadly the pub is shut!) before a final climb up into Machen Woods followed by a downhill trail to the finish line.
Marathon Route
The marathon has a tough start to the second section, after completing the half marathon route, a very steep climb to the Rhymney Valley Ridgeway. Once at the top there is good track running for several miles, which should warm you up! You'll then head downhill toward Wyllie, and onto the Sirhowy Valley Walk. There's plenty of downhill single track to enjoy in this section! After a few tricky turns and a steep ascent back onto the ridgeway, good running again takes you to the highest point of your day, and the Machen Mountain / Mynydd Machen trig point. A quad-bashing descent will take you back to Machen where you'll pick up your reward for completing a challenging but hugely rewarding marathon.
Note: The half course will be fully marked. The marathon route will require self navigation, though there will be marshals at critical junctions to support you.
What you get
A professionally run event, with full medical support, with a fully mark half marathon route, with helpful marshals to support you on your way.
Every finisher will receive a finishers medal, and there will be trophies for:
- 1st, 2nd, 3rd Male
- 1st, 2nd, 3rd Female
- 1st Male Veteran (over 45)
- 1st Female Veteran (over 45)
Race Details
Date: 28 November 2026
Marathon race start: 8:00am
Registration: 7:10am to 7:40am
Half marathon race start: 9:00am
Registration: 7:45am to 8:30am
There will be a kit check at registration – no kit, no entry. Full kit list information can be found here.
Race venue:
Machen Welfare Ground,
Tyn-y-Waun Road,
Machen,
CF83 8LA
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Costs
Half marathon - £40
Marathon - £50
Cut offs
Half Marathon:
- Race start: 9:00am
- CP1 cut off: 12:00pm (6.8 miles) [3 hours]
- CP2 cut off: 1:30pm (10.5 miles) [4.5 hours]
- Race finish: 2:30pm (14ish miles)
Marathon:
Overall time limit of 8 hours for the full marathon route.
- Race start: 8:00am
- CP3 cut off: 12:00pm (14 miles) [4 hours]
- CP4 cut off: 12:45pm (16 miles) [4.75 hours]
- CP5 cut off: 3:00pm (22.5 miles) [7 hours]
- Race finish: 4:00pm