Google Maps has a neat feature that lets you calculate distance between two points anywhere on the Earth - you could use this to measure the approximate distance between two cities or to calculate the size of a local football field or to know how far is your new office from home.
In the above example, Google Maps helps us measure the length of Manhattan Bridge between Brooklyn and New York that lies over the river.
To measure distances using Google Maps, go to google.com/maps and search for any location. Now right-click with your mouce and choose the “Distance Measurement Tool” - now select any two points on the map with your mouse and the distance will appear in miles (or kilometers).
Google Maps uses straight lines to calculate the shortest distance but if you are looking for more accurate numbers, trace the complete route by clicking at all the curves and deviations as below:
In this example we measured the distance between the car parking of Taj Mahal and the actual monument - one has to cover 1.4 km on foot before he gets in.
You can also use the Distance Measurement tool in Google Maps to calculate the perimeter of places by tracing the path along the boundary.