I tend to like the rolling countryside nearby, but there are long pan-flat routes available to me as well.
I live downtown in a city of about half a million people. The most prominent feature of the city is 100-150m high escarpment that runs right through the middle of town. I say "prominent" because pretty much every route I choose involves climbing it. There are lots of different routes to climb it, with different characteristics. One is only a single km long and has 10-15% grades. Another is an 8km long former railroad track and has a grade of about 3%.
In 2003, I got to watch Erik Zabel, Robbie McEwan, Victor Hugo Pena and 150 of their friends and enemies climb it 40 times during the World Road Race championship. Some doper named Astarloza won it.
