If you travel around, one question allway comes to your mind: Can I get to and from the places I'm considering quickly and easily?
The maps on the mySociety page show one way of answering that question. Using colours and contour lines they show how long it takes to travel between one particular place and every other place in the area, using public transport. They also show the areas from which no such journey is possible, because the services are not good enough.
...
mySociety: Travel Time Maps