Here is the elevation chart for Trans Iowa (320 mile non stop gravel race). It averaged out to 5,000 feet of gain per century. But it was the toughest 5k per century I ever remember doing--steep continuous rollers on gravel. Starting elevation was 741ft and max elevation was 1050 ft.



That was much harder and much more painful than doing a long long 30 mile climb.



So while I love 10,000 feet of gain centuries I HATE short steep rollers. And while I used to say 5,000 foot centuries weren't hilly centuries I am now a convert.