Are you concerned about the overall elevation, the steepness of climbs and descents or the total amount of climbing in a day?
can I say D All of The Above? :-)
But primarily it is Steepness of Climbs that concerns me. (plus possibly cold temperatures which I find can sap my energy fast - but I'll have gloves, hat, longs and a jacket)
if I was just riding solo, I would have no concerns (except the cold)
My Bike Friday is geared to climb
but towing a trailer is a different animal.
on past tours I have faced steep pitches (I don't remember the grade) that while short have almost broken me.
that trailer goes from moving well to feeling like a stone anchor.
One, was only about 200m long (in town in the Canary Islands and I had to get up it to get to my hostel) I might have had to push the rig up the last stretch. I can't remember now.
But you are correct. it looks slow and steady. if I just keep doing Left Right Left Right I find I can surmount almost anything.
But it's also the unknownness of it all that makes me anxious. I'll have just got off the plane. I am not in End Of Summer riding condition.
But I am probably just being a Nervous Nelly.