BT Sport Cardiff Arms Park staged the Grand Depart as the riders set off on their 500-plus mile journey to the Dutch capital.
Cardiff Blues chief executive Richard Holland, Owen Williams’ father Huw, assistant coach Paul John and former teammate Macauley Cook were all among the riders.
Stage One of the challenge will see the party pedal all the way from our iconic home in the Welsh capital to north of Swindon.
And over the next four days they will spin their wheels all the way to the I Amsterdam sign, clocking up as much as 85 miles a day.
The ride aims to raise both funds and awareness for the #StayStrongForOws campaign which supports former Cardiff Blues and Wales star Owen Williams.
Owen suffered a significant spinal injury representing the region in the Singapore Club 10s two years ago.
He is currently back in his hometown of Aberdare where he continues to adjust to his life-changing injuries.
Holland said: “It’s great to finally get in the saddle for another ride from Cardiff in support of Ows.
“Many of us cycled to Paris last year and jumped at the opportunity to take part in another for a cause that is so close to our hearts.
“I’m sure it will be very difficult at times and there will be a lot of sore bodies at the end but it pales into insignificance compared to the challenge Owen has, and continues to, face.
“All the money raised goes towards the purpose-built house for Owen which is currently being constructed in Aberdare.”
Owen will join the riders in Amsterdam and you can follow their progress both on the club website and social media.
To support the campaign, please visit www.justgiving.com/staystrongforows
Day 1 – Cardiff to Wiltshire 113km/ 1043 elevation
Day 2 – Wiltshire to Welwyn Garden City 140km / 909 elevation
Day 3 – WGC to Harwich 138km/810 elevation
Day 4 – Hook of Holland to Amsterdan 92km/304 elevation.