I'm thinking CP4 has the riders going all the way down to get their stamp and then straight back up again to the start of the parcours?
Looks about ~600m descent and ascent.
I had guessed it was a glitch in my map and the checkpoint was showing up wrong. Seems not. An 800m down and back again would be pretty tough, both physically and mentally. Especially for those further to the back of the field starting to feel deep fatigue by the time they get to this checkpoint.
I'm thinking CP4 has the riders going all the way down to get their stamp and then straight back up again to the start of the parcours?
Looks about ~600m descent and ascent.