Become a Kosi Challenger

Join us for the 2026 Kosi Challenge on Friday 13 and Saturday 14 March!

Choose the day that suits you to climb from Thredbo Village to the summit of Australia's highest mountain, Mt Kosciuszko, or join us virtually.

It's more fun with friends, so get together a team and take on the challenge, while raising funds to help us continue doing whatever it takes to support people affected by rare and less common cancers. 

5,000

people have taken on the Kosi Challenge since the inaugural event in 2013.

$5.2 million

has been raised to support people diagnosed with rare and less common cancers.

22,000 kms

climbed in 2025 for Australians impacted by rare and less common cancers.

What is the Kosi Challenge?

The Kosi Challenge is Rare Cancers Australia’s (RCA) major fundraising event, held in March each year since 2013.

It sees people unite from across Australia, including patients and families, to climb to our country's highest point, the summit of Mount Kosciuszko to raise much needed funds and awareness for people in Australia affected by rare and less common cancers.

No one in Australia should have to go through their cancer journey alone. That is why we walk the journey with those impacted.

Take on the challenge for Australia's forgotten patients

The Kosi Challenge has now grown to run over two huge days in Thredbo. You can choose to climb on either Friday 13 or Saturday 14 March 2026.

Attend In-person

Encourage your family, friends, and colleagues to register a team, raise vital funds and awareness for rare cancers, and make it a weekend to remember!

Challenge yourself virtually

Can’t make it to Thredbo? You can still show your support and take on the challenge virtually – by walking or running 21km wherever suits you on the Kosi Challenge weekend.

$2,831

Help us to reach our $750,000 goal

  • Alessandra just donated $106
  • Adam Bough just donated $106
  • Lynn Wright just donated $23
  • Deb Bough just donated $6
  • Cherie Wilson just donated $35
  • Dael Strauss just donated $54
  • Annie Porter just donated $106
  • Carrie Taylor just donated $28
  • Carrie Taylor just donated $28
  • Lorna Fenech just donated $54
  • Asa just donated $53
  • Jo Bentley just donated $6
  • Helen Jarvis just donated $64
  • Camila Conti just donated $50
  • Margie Taylor just donated $50
  • Sarah, Joel and Josie Baldwin just donated $105
  • Diana Murray just donated $270
  • Anne O'Donnell just donated $6
  • Anonymous just donated $38
  • Kate Bruce just donated $64

Leaderboards

All

Top Fundraisers

Top Teams

No person should have to go through their cancer journey alone.

That's why we walk with them, and you can too.

In Australia, someone is diagnosed with a rare or less common cancer every 12 minutes.

Diagnosis can be delayed, survival outcomes are poorer, and people with rare or less common cancers can face exorbitant costs for treatments that are not subsidised for their cancer type. 

Coupled with a lack of information and support, it can be a very lonely and uncertain journey.

The Kosi Challenge unites a community of support with a common purpose - ensuring nobody has to walk alone.

Top Kosi FAQ’s

How can I participate in the Kosi Challenge?

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In-person

By joining us on Friday 13 or Saturday 14 March 2026 to climb the iconic Mt Kosciuszko.

Virtually

By walking or running 21km across the two days of the Kosi Challenge, wherever you are in Australia or around the world!

Along the way, you're encouraged to fundraise as much as possible to help us continue doing whatever it takes for people affected by rare and less common cancers. 

When is the event and what time does it start?

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The in-person Kosi Challenge is an all-day event on Friday 13 or Saturday 14 March 2026. Groups leave every 15 minutes from 7am to 9.30am each morning. If you plan to take the chairlift, you should choose a start time from 9am onwards.

Due to the high number of participants expected, it is crucial that you arrive 20 minutes prior to your start time to allow for check-in and event briefing.

Please note: A chairlift ticket is included in your registration.

The Virtual Kosi Challenge will take place on the same dates as the in-person event. You can complete your walk, hike or run at any time during this period, either in one go or broken up across the two days.

What is the difference between the Friday and Saturday events?

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Both days follow the same format – challengers begin their staggered starts from Thredbo Alpine Hotel in the morning, descending by early afternoon. After some food to recharge and a shower to refresh, challengers are invited to come together again in the early evening to celebrate the collective difference we’ve made for Australians impacted by rare cancer.

On Friday evening, join us for the Kosi Kick-off in the Kosciuszko Room of the Thredbo Alpine Hotel. Here, you can share your stories from the day's climb, meet some of the Saturday Kosi Challengers, connect with the Rare Cancers Australia team and learn more about the impact of your fundraising. 

Stay until Saturday evening for the Kosi Awards Ceremony in the courtyard outside the Thredbo Alpine Hotel. We'll recognise our highest fundraisers, hear from those impacted by your fundraising, remember those we've lost, and enjoy a drink in the company of new friends.

How do I register and when do registrations close?

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Please visit the registration page.

Registrations for the in-person event close at 12pm on Friday 6 March 2026, unless sold out earlier.

Registrations for the Virtual Kosi Challenge will remain open until Saturday 14 March 2026.

What are the costs?

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Adults attending in-person

Registration: $99.00

Children (under 17) attending in-person

Registration $50.00

In-person registration covers costs such as event insurance, promotion and park fees. You'll also receive a Rare branded cap on the morning of your climb, and have the opportunity to unlock other merchandise rewards as you reach fundraising milestones.

Discounted accommodation is available for participants. Please contact Nicole Thrum, Events & Groups Manager, Thredbo on 02 6459 4184 and mention Rare Cancers Kosi Challenge to receive your discounted room rate.

If you drive your car into the National Park you will be required to purchase a Parking Pass. The cost is currently $17.00 per car per day. 

Adults and children participating virtually

FREE

This year for the first time, registration for our Virtual Kosi Challenge is free. You'll receive Rare branded merchandise as you reach specified fundraising milestones. 

What does my registration fee cover?

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The in-person registration fee covers administration costs, event insurance, associated fees and promotion. You will also receive a Rare branded cap on the morning of your climb. 

Registration for the Virtual Kosi Challenge is free.

In-person and virtual participants can both earn merchandise rewards at specified fundraising milestones.