I have just returned home from a minicruise to Oslo with the ship Pearl Seaways :-)
It sails during the night to Oslo. Then you get the day there, and then sail back in the night again to Copenhagen.
It's actually a lot of fun and my boys really enjoyed themselves.
Anyway in Oslo there is a park called Vigelandsparken. It's a cool sculpture park with lots of steps! So I figured it would be a good idea to run up them a little to get in some hill training. My older son joined me and was just as quick at running up as I was!