Advanced Camera Movement

Greetings! I hope you can help me with my problem:
I’m trying to make a little movie, starring a camera moving through a very simple city. I need to find a way to move and rotate the camera through the city. Key framing the movement makes it really bumpy. I have also tried doing it with curves, however I can’t find a way to slow down or speed up the movement with a Follow Path constraint. I can imagine it might be solved with the graph editor, I only don’t know anything about it.
What do you suggest to move and rotate the camera, smooth and with different speeds?

Salutations
PsychoTurkey

you can change the resolution ( number of steps ) in your path curve. this will slow it down or speed it up.

Thank you, but that is not what I mean: I want to have different speeds on different moments (e.g. stand still before crossing a street, or running away), your solution would change the speed along the entire curve. Maybe it can be achieved using multiple curves, however I cannot find out how.

you can give it multiple paths / constraints, set to different frame ranges, and keyframe the influence. I can give a more in depth explanation if needed.
(edit) while trying to set up an example, I ran into a bump, so I am trying to figure out what is going wrong. It should work though. I just have to figure out what I did wrong.
(edit) I found this explanation, at stackexchange, of two slightly different approaches. the second one is basically the same as my own. Still trying to get mine to work though…not sure what the deal is.

You may like this camera rig add on. https://vimeo.com/85884210

I find it very useful and more intuitive then using curves/paths/whatever.

Modron: thanks, this is exactly what I was looking for.
DanPro: although this doesn’t give me the movement options I need, it’s definitely helpful!