South London hills

Now, here's where I'm confused, although I've not actually ridden up Vanbrugh Hill and perhaps I should add it to my list of things to do before I die, because I regularly ride up the hill in Greenwich Park and to me it's a walk in the park - actually it's a ride up a hill in the park, but I digress - so how is it that when both hills basically run from the same fairly level road at the bottom to as near as damn it the same level at the top that Vanburgh Hill looks to be twice as high as the hill in the park, huh?

It just kicks up sharply just before the old nurses home on the right as far as about ulundu road then flattens off - short and sharp.....