South Wales 100 and 50

The SW100 is a 105mile ultra-trail footrace starting and finishing in Cardiff, crossing the South Wales Valleys and the Brecon Beacons!  It is a demanding test of endurance over varied and challenging terrain and is only suitable for experienced and competent ultra-trail runners. The route has approximately 6400 meters of ascent and is over 90% on trails. This is a tough course, with only 25% of participants completing the course in 2016!  It is a UTMB qualifying race eligible for 6 UTMB pionts.

The SW50 is the second half of the SW100 route. Starting from the Pont ar Dawe Car Park at the foot of Pen y Fan, you will run over the main Brecon Beacons range brefore running back to Cardiff, it has over 3200 meters of ascent.  It is also a UTMB qualifying race eligible for 4 UTMB pionts.  

The SW100 course starts at 1900 on Friday 23rd June 2017. The SW50 starts at 1030 on Saturday 24th June 2017.

New for 2017 we have a SW100 Walkers/non-competitive start time which starts at 1500 on Friday with an overall cut off time of 44 hours.  

The Route

The race starts in Cardiff, the capital city of Wales, briefly heading North out of the city to Castel Coch. On a clear day, from the top of the first climb, Mynydd Y Garth, you can see the highpoints stretched out of the entire circular route you are about to conquer - even Pen Y Fan looming in the distance!  From here you head West, picking up trails along the Ridgeway route towards Ogmore Vale before heading North again to the top of the Bwlch.  You will cross the Valleys of the old mining communities of Treorchy and Hirwaun before heading into the Brecon Beacons National Park. Some stunning forestry trails take you to the more exposed summits of Fan Llia and Fan Frynych, as you then drop down to cross the A470 and the Storey Arms at the half way point.

It is here the SW50 mile route joins the SW100, starting at the foot of Pen Y Fan.  Both routes head up the main Brecon Beacons Range of Corn Du, Pen y Fan, Cribyn and Fan y Big before the long descent to Talybont reservoir. From here the last big climb in the Beacons is Tor y Foel before turning back towards Cardiff via Tredegar, the Rhymney Valley and the rolling hills surrounding them.  A final push over Caerphilly Mountain and Crag yr Alt brings you back to Castle Coch and a easy jog to the finish.

For a map of the route and gps file click here

You can download the route gps from mapometer by clicking actions then export.

For ITRA map and website click here

For a more detailed route decription click here.

Event Base / Race HQ

The event base will be at the following address.
The Cardiff Harlequins Rugby Club,
The Diamond Ground
CF14 7JN


There will be 10 manned checkpoints with the usual variety of energy foods and drinks. The checkpoints at mile 26, 50 and 75 (25 on the 50) will provide a substantial meal option. Exact details of what you will find at each checkpoint will be provided before the race allowing you to plan an effective nutrition strategy.  There will be a number of control points located on the course (for example the top of Cribyn) to ensure competitors follow the course correctly and to aid safety, they are not manned.

Time Limit

There is a 40 hour cut-off time for runners to complete the entire SW100 course. There is a 24 hour cut off time for runners to complete the SW50 course.

New for 2017 we are offering a 'Walkers Start', which allows for a 44 hour time limit for the SW100. For the walkers start you will set off at 3pm on Friday giving you an extra 4 hours to complete the course. Please note that if you decide to take the walkers start time and set off to quickly you will have to wait to go through the first few checkpoints as they will open based off a walkers speed. If you take the walkers start this is non-competitive which means you will not be elegable for prizes in the race!  

Route finding and navigation

The route is self navigation and you will receive a marked map with the route on it, a comprehensive road book with route description in it, and a gpx file of the route.

Organised Recces

There are four organised recce days throughout the year. Details can be seen here.

Participant entry requirements & experience

Both routes require participants to be self-sufficient, which means you must be able to complete the route as if without any support, carrying the appropriate compulsory kit and food and water beween checkpoints.  To enter the SW 100 you need to have experience in Ultra trail racing and as a minimum you should have completed at leat one 50 mile event of similar nature, examples will be asked for on the entry form. You should be able to run comfortably and navigate at night. You will need to be totally self-sufficient throughout the event and able to make sound mountain judgment.

For the SW 50 entrants will need to be able to navigate the route using map and road book. It is likely you will be finishing in the dark so you will need to be able to navigate and run in the dark. You will need the physical fitness to complete the event carrying the compulsory kit including food and water between checkpoints. There is no qualifying necessary for the SW50 but you must have gained the required skills and fitness levels to complete the course safely. Warning-This is a tough course with a 65% completion rate in 2016!  

Gaining the Relevant Skills & Fitness

For more information about gaining the navigation/mountain skills and the relevant fitness levels please contact us. We can provide comprehensive fitness programmes and navigation training by highly experienced fitness professionals and mountain leaders. We can also provide custom route recce to individuals or small groups on days that suit.

Solo, Pair or Team

You can enter the event as an individual, a pair or a team of up to four. All members of pairs or teams must complete the course staying together. There is no relay option for the course.

What your entry fee includes

  • Checkpoints with refreshments
  • Event T-shirt
  • Event Medal
  • Camping at race HQ for Friday and Saturday night
  • Toilets, showers and changing facilities
  • Post Event Meal
  • Bus Transport from Cardiff to Brecon Beacons for SW50 competitors
  • Physiotherapy and First Aid Cover

Compulsory Kit

As is custom in these types of events there is a compulsory kit list that must be carried for your safety. Exact details can be found here.

Registration & Briefing

All entrants will be required to attend registration and briefing at the event HQ in Cardiff at the times outlined below.

Event Provisional Timings

1000 Campsite Opens
1200 Registration Opens for 50 & 100 competitors
1730 Registration closes
1730 SW100 Briefing
1900 SW100 Start
1930 Registration re-opens for SW50 competitors
2200 Registration Closes
2300 Campsite Closes


0630 Registration Opens SW50
0745 Registration Closes
0800 SW50 Briefing
0900 Busses Depart for Brecon Beacons
1030 SW50 Start
1500 First 100 Finishers expected (20-22 hours)
1830 First 50 Competitors expected (8 hours)


1100 Last finisher for SW100
1100 Last Finisher for SW50
1200 Presentation
1400 Campsite and Race HQ closes


SW100 £90
SW50 £70

You can select the appropriate options when you sign up to the event online.


Race terms and conditions can be viewed here

Enter Online


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