In Civilization 4, you had to connect an improved resource to your capital via roads/rivers. Is there any such requirement in Civilization 5? Or is it enough to just get them within your territory?
They'll just need to be in your territory. Building roads is only helpful in between cities, due to the high maintenance cost. The age of endless road-sprawl is finally at an end!
It is important to note that you'll need to build the corresponding improvement on top of the resource to "capture" it.