100km, 50km and 80km Relay Marathon Event
13 Sept 25
After the inaugural seasons success, the Collie River Ultra (CRU) Marathon is back with epic trail running adventures for everyone!
All events are supported by a dedicated trail crew ensuring your safety and enjoyment every step of the way.
The charming country town of Collie in Western Australia has had $10 million invested in creating a network of stunning adventure trails for all to enjoy. This is the perfect opportunity to run through Australian bushland with full service race support.
All events are supported by a dedicated trail crew ensuring your safety and enjoyment every step of the way.
Ready to Take On the Challenge?
Choose your event and lock in your spot below:
Solo 100km
Solo 50km
Relay 80km
Australia’s best trail and adventure destination. The trails wind through stunning:
- jarrah, marri, yarri forests
- across bridges, over logs
- granite outcrops
- views of Collie River Valley
- wildflowers
These are the best running trails we’ve found, and we’re inviting you to see for yourself!
About Perth Trail Series:
CRU100 is proudly organised by Perth Trail Series, Western Australia’s leading trail running event organisation. With over 90 events annually, their experienced team and passionate volunteers deliver safe, inclusive, and rewarding trail experiences with a friendly community vibe.
Expect expert course marking, excellent support, and a celebration of the great outdoors at every event.
Full-Service Race Support:
All CRU100 events start and finish near Collie town, with the start at the Collie Cemetery and then finish at Collie Golf Club.
Runners enjoy a fully supported experience with:
• Bus transfers to start line
• Multiple aid stations stocked with food, water, and medical support
• Well-marked and marshalled trails
• Spectator-friendly viewing points
Your safety and comfort are our top priorities every step of the way.
There’s an event for everyone with SOLO 100km, SOLO 50km, and RELAY 80km event where you can hit the trails with 2-5 runners to complete the course. For more details about each event, click on your preferred event category below.
The 100km is on the Wiilman Bilya Trail and starts at the Collie Cemetery.
On the Final Leg, there is an opportunity to drop down to 80km and still receive a finish time.
Buses to Start Lines:
All runners for the 100km will be transported by bus from the Collie Golf Club to their respective start lines.
100km Start (6:00 AM): Buses depart at 5:00 AM, 5:15 AM, and 5:30 AM. Runners who still need to register or drop off gear must catch the first or second bus.
Brief summary of the terrain types found:
- Leg 1: Easy running on a firm base. Minimal technical aspects. Flat and fast.
- Leg 2: Great running on firm, hard packed trails. Mix of wide and single trail. All Undulating.
Leg 3: The Dam Wall leading onto beautiful single track, flowy firetrails and forest. All Runnable.
Leg 4: Incredible running with all trail types. Some Climbing – mainly on single trail paired with stunning views. Trails have a firm base with some technical aspects.
Leg 5: Good running with all trail types. Mainly on trails which mostly have a firm base and hard pack dirt. Some technical aspects after the hanging bridge and heroes welcome at finish.
CRU100: 101.3km +/- 2000m
Transition 1: 12.4km ; Last Runner Expected at: 8:23am
Transition 2: 26km ; Last Runner Expected at: 10:59am
Transition 3: 46.5km ; Last Runner Expected at: 3:45pm
Transition 4: 64.1km ; Last Runner Expected at: 6:17pm
If you fall behind these last expected runner times, at 73.7km you’ll be directed to stay on the final relay Leg and finish your race at 81.3km.
CRU100 HARD CUT OFF: 73.7km
*If you’re not here by 7pm, you’ll be directed to stay on final Leg and finish your race at 81.3km. This is based on consistently maintaining a 10:30min/km pace.
FINISH RELAY: Last Runner Expected at: 9:13pm
FINISH CRU50: Last Runner Expected at: 8:06pm
FINISH CRU100: Last Runner Expected at: 11:43pm
The 50km course starts on the ICONIC Largest Dam Mural in the Souther Hemisphere and finishes in the town of Collie all taking place surrounded by wildflowers on the Wiilman Bilya Trail! It’s all runnable, making it perfect if it’s your first 50km!
Buses to Start Lines:
All 50km event will be transported by bus from the Collie Golf Club to their respective start lines.
50km Start (9:30 AM): Final shuttle departs at 8:30 AM.
Brief summary of the terrain types found:
Leg 1: Epic Start leading onto beautiful single track, flowy firetrails and forest. All Runnable.
Leg 2: Incredible running with all trail types. Some Climbing – mainly on single trail paired with stunning views. Trails have a firm base with some technical aspects.
Leg 3: Good running with all trail types. Mainly on trails which mostly have a firm base and hard pack dirt. Some technical aspects after the hanging bridge and heroes welcome at finish.
CRU50: 50km +/- 1,051m
Transition 3: 20.5km ; Last Runner Expected at: 3:45pm
Transition 4: 38.1km ; Last Runner Expected at: 6:17pm
FINISH RELAY: Last Runner Expected at: 9:13pm
FINISH CRU50: Last Runner Expected at: 8:06pm
FINISH CRU100: Last Runner Expected at: 11:43pm
The Relay 80km is on the Wiilman Bilya Trail and starts at the Collie Cemetery.
On the Final Leg, there is an opportunity to drop down to 80km and still receive a finish time.
Relay Teams: No buses provided. Teams must arrange their own transport between checkpoints.
Brief summary of the terrain types found:
- Leg 1: Easy running on a firm base. Minimal technical aspects. Flat and fast.
- Leg 2: Great running on firm, hard packed trails. Mix of wide and single trail. All Undulating.
Leg 3: Epic Start leading onto beautiful single track, flowy firetrails and forest. All Runnable.
Leg 4: Incredible running with all trail types. Some Climbing – mainly on single trail paired with stunning views. Trails have a firm base with some technical aspects.
Leg 5: Good running with all trail types. Mainly on trails which mostly have a firm base and hard pack dirt. Some technical aspects after the hanging bridge and heroes welcome at finish.
Relay Total: 76km +/-1600
Transition 1: 12.4km ; Last Runner Expected at: 8:23am
Transition 2: 26km ; Last Runner Expected at: 10:59am
Transition 3: 46.5km ; Last Runner Expected at: 3:45pm
Transition 4: 64.1km ; Last Runner Expected at: 6:17pm
FINISH RELAY: Last Runner Expected at: 9:13pm
FINISH CRU50: Last Runner Expected at: 8:06pm
FINISH CRU100: Last Runner Expected at: 11:43pm
All items listed below are mandatory for participants in the 100km, 50km, and 80km Relay events.
MOBILE PHONE
- Must be fully charged at the start.
- If your phone doesn’t hold charge well, carry a small power bank (e.g., Comsol 2200mAh – lightweight and compact).
- Telstra SIM + 3G mode recommended for best coverage.
- Install the Emergency Plus App with GPS enabled.
- Save this number in your contacts:
PTS Race HQ: 0423 729 949
RACE BIB NUMBER
- Must be worn on your front and visible at all times, even over jackets or vests.
- Race belts are useful for easy changes at aid stations.
- Don’t fold or pierce your bib — it contains your timing chip.
FIRST AID KIT
Your kit must include at least:
- 1x Compression Bandage
Minimum size: 7.5cm wide x 2.3m long (unstretched)
You’re welcome to include additional items, but the compression bandage is the minimum requirement.
SPACE BLANKET
- Carry a thermal (space) blanket at all times.
BUFF OR BEANIE
- One Buff or Beanie must be carried.
- A Buff will be provided in your race pack.
HIGH-VISIBILITY VEST
- Must be your outermost layer, worn over your pack.
- From 4:00 PM, you must carry it.
- From 6:00 PM, you must wear it.
HEADLAMP + SPARE BATTERIES
- From 4:00 PM, all runners must carry a headlamp and spare batteries.
- Phone lights do not meet requirements.
- Acceptable alternatives to spare batteries:
- A second charged headlamp, OR
- A power bank that can recharge your headlamp
WATER
- You must have capacity to carry at least 1 litre of water.
- Bring a collapsible cup for use at aid stations (no disposable cups provided).
- Water and electrolytes will be available in 15L containers at transition points.
WATERPROOF BAG
- Use a zip-lock or waterproof bag to store:
- Phone
- Headlamp
- Other sensitive items
- Optional: Carry an extra bag for your thermal top and Buff to keep them dry.
WEATHER JACKET & THERMAL TOP
- Both must fit properly and be carried from the start.
- Jacket should be waterproof (taped seams recommended).
- Even in dry conditions, prepare for emergencies — if you’re delayed or injured on course, it can get cold quickly.
Available for 100km and 50km Solo Runners
Drop bags are a great way to access your personal gear, food, or clothing throughout the race. Use them strategically at key transitions to keep yourself fuelled and moving strong.
Drop Bag Guidelines
Maximum Size: 30cm x 30cm (Ziplock freezer bag)
Label Clearly: Must include your Name and Race Bib Number
Drop Bag Locations
CRU100 Solo Runners:
Transition 1 – 12.4km
Transition 2 – 26.0km
Transition 3 – 46.5km
Transition 4 – 64.1km
100k Aid – 73.9km
100k Aid (Return) – 93.5km
CRU50 Solo Runners:
Transition 3 – 20.5km
Transition 4 – 38.1km
Notes:
- You can mix drop bags and aid station supplies – plan what works best for your race.
- Unclaimed drop bags will be disposed of 1 week after the event unless you contact us to arrange collection.
- Drop bags will be available to collect to 2 hours after transition closes.
A good support crew can lift your spirits and keep you moving forward!
Crew Tips:
- Go over your aid station plan before race day
- Remind them to bring positive energy — it helps more than you think!
Crews can assist with:
- Nutrition & hydration
- Gear swaps
- Motivation and check-ins
Seeing a friendly face at an aid station can be the mental boost you need to push on!
These items aren’t required — but they can really help, especially if it’s your first ultra.
Hiking Poles
Pros: Improve balance, reduce strain on climbs/descents
Cons: Can be bulky — try foldable ones
Tip: Train with them before race day
Thermal Gloves
Useful for cold starts or night running
Some models work with phone screens
Nutrition
Carry your go-to energy foods
Aid stations have a variety, but don’t rely solely on them
Popular items: gels, potatoes, watermelon, chocolate, Red Bull
Comfortable Clothing
Choose gear you’ve trained in
Prioritise comfort and avoid irritating seams
Useful extras: hats, sunglasses, gaiters, compression gear
If you click on the square in the upper right corner you can open it in your maps, and use it to view all the incorporated information about the transitions and facilities, such as coffee van, toilets, and parking designated with icons on the map.
Please follow driving directions below, and only go to the places on the course that we advise.
If you click on the DIRECTIONS text in each section, it will open those driving instructions in google maps on your phone / tablet.
You’ll also see toilets, showers, and coffee if you open the Map, and click on the icons!
RACE LEG #1
Head out of Collie, towards Bunbury, on the Coalfields Highway.
Just past the 11km mark, prepare to turn LEFT onto an unnamed road. This road starts just as the wire roadside barriers finish.
PLEASE BE CAREFUL MAKING THIS TURN AND GIVE FOLLOWING TRAFFIC AMPLE INDICATION, AS THE SPEED LIMIT HERE IS 100km/h.
Travel down this gravel road (2wd suitable) for about 300m and you’ll come to a cross -roads which is the transition / aid station.
Please make a RIGHT turn onto the crossroad here, and park along the side. You’ll continue down this road to exit the aid station back onto Coalfields Highway.
- Please park responsibly in this area, ensuring other traffic can come and go.
RACE LEG #2
Continue down the gravel road you parked on for 2.5km. DO NOT go back the the entry road, as there may be other cars coming into the Aid Station.
This will get you back to the Coalfields Highway. Turn LEFT here, exercising the same caution as before.
After 3km on the Coalfields Highway, take the LEFT turn onto the Wellington Dam Road.
Follow this road for 11km, and you’ll come to the Kiosk at the Dam parking on the RIGHT.
Overflow parking is another 100m down on the right, with the Aid Station being opposite this, and even more parking another 100m down at The Quarry.
Make sure you stop and get a photo of one of the largest dam murals in the Southern Hemisphere, if not the World!
As always, park responsibly if you’re getting out for a photo….
From your parking location at Wellington Dam, head back out of Wellington Dam the way you came in.
After 6.5km, turn LEFT onto River Road, which takes you down to Honeymoon Pool.
Cross over the bridge here and continue up River Road (one-way).
River Road will bring you out to Pile Road.
Turn LEFT and follow Pile Road / Mungalup Road (bitumen) for approximately 20km.
Turn LEFT into Kelly Road (gravel) and follow this for 3km.
Please park as far as you can on the left hand side of the road, BEFORE you get to the aid station, then walk the last 50m or so into the aid station.
RACE LEG #4
From your parking at Kelly Road, please go BACK down Kelly Road the way you came in, to avoid interference with the runners leaving the aid station.
Once back at Mungalup Road, turn LEFT.
Just past 5km along Mungalup Road, turn LEFT onto Palmer Road (gravel).
Continue 8.2km along Palmer Road, then turn LEFT into Connell Road.
The aid station parking is about 1.5km down Connell Road.
PLEASE BE AWARE: LEG #5 actually crosses Palmer Road, about 3.5 – 4km after you turn off Mungalup Road.
DRIVE CAUTIOUSLY in this area as runners will be crossing.
These are directions to the CRU100 Aid Station, which is about 10km from the finish for the CRU50.
There are also other opportunities to see runners in action, as from this point, the remainder of the course crosses or runs parallel with many of the roads around Collie.
PLEASE NOTE: Once the 100k runners commence their 20k diversion, there will be limited opportunity to see them again until they return to the Aid Station.
From this aid station, please go BACK UP Connell Road, and down Palmer Road again to Mungalup Road.
Once back at Mungalup Road, turn LEFT.
Continue 3.4km along Mungalup Road and you’ll cross a bridge.
As you get to the other side of the bridge, you’ll see the Bibbulmun Track stairs coming up to the left hand side of the road.
For the best parking, continue up the road about 150m, make a SHARP RIGHT onto a gravel road to come back towards the river.
Park, cross the road with caution, and follow the Bibbulmun Track about 200m to the CRU100 Aid Station – marked in red.
These are the directions from the CRU100 Aid Station, to the finish line.
Please follow any event signage you may encounter as you approach Collie Golf Club and the finish line.
Please ensure you don’t block business or private residence driveways and access routes.
Most importantly of all, come and enjoy the atmosphere and cheer your runner(s) home! What an incredible adventure they’ve undertaken, one that YOU have been part of, and one that you’ll BOTH remember for a lifetime!
A HUGE shout out goes to our Partners, Sponsors and Crew!
We acknowledge the traditional custodians throughout Western Australia and their continuing connection to the lands and trails on which we run. We pay our respects to ancestors and Elders, past – present – emerging.
At Perth Trail Series we respect our environment. On the trails we acknowledge the continuing connection and we’re committed to honouring Australian Aboriginal and Torres Strait Islander peoples’ unique cultural and spiritual relationships to the land, waters and community.
Keep in touch with early entry call outs for all of our trail series events. With spots selling out in some events, it pays to run ahead of the pack and register early.