Superman Returns

You must travel for a total accumulated distance of 10,000 miles. Despite the name of the achievement, the total includes the amount of miles that you walk. However, flying is much faster.

This achievement will take a long time to earn though (I'm talking upwards of 8 hours after you've finished everything else), so it's best to tape down the fast fly button, wrap a rubber band around the left stick and make Superman fly around in circles all night while you get some sleep. With any luck, you should wake up to find the achievement unlocked, assuming your 360 hasn't turned into a charred heap of molten plastic and silicon. Just make sure that you're using either a wired pad or your wireless pad is connected via a play and charge kit, otherwise the pad will automatically turn itself off after about 10 mins.

Here is another installment of ShutTheCakeHole's Math Time:

In doing some calculations, here is the approx. time and travel as you circumvent the map:

Times for 3 laps:
Lap 1 - 3:00.3
Lap 2 - 2:59.8
Lap 3 - 3:02.2
Average time for a round trip - 3:00.1

A lap is equal to the outer rim of the map.

Text description: start at the tanker in the south tip of the map (industrial area), head west and round the cape where there is a lot of boats docked by two docking stations, round the cape and head east right by the steep incline of the city and outer highway, sightly veer to the right to round the eastern most island (connected by a 'Golden Gate Bridge' type bridge), with a wide round about line up with the industrial island in the distance and following the coast, finish off back at the tip of the tanker - 1 lap.

Total distance traveled for a single lap around the city (sea level) - 40.25 miles. (approx.)
Number of laps total for the entire 10,000 miles - 249 laps (approx.)
Taking in the consideration the time for a lap multiplied by the number of laps it takes for total distance (rounding):

3:00 minutes X 250 laps = 12:30 hours/minutes total time for achievement.

This has been another installment of ShutTheCakeHole's Math Time. Please be aware this is approx. values and is only used to give you an idea on how long it takes to get this achievement, out-of-box. Usually, round about 1500 miles is achieved through normal game play plus the walking time (100 miles approx. for game play). This leaves around 8,400 miles left for flying 10:26 hours/minutes left. As a completionist, I know the answer to the question - here goes. Is it really worth 10 hours and 26 minutes for 30 point gamer score? Yes.

Additional note: It is actually 60 gamer score guarantee - With 30 points for this achievement, 30 additional points are added due to time.

Hope this helped with your decision. Cheers and good luck!