There is no documented and approved method at the moment to access the Google Maps Directions API via an HTTP request (update: Google added walking and driving directions via web services in May, 2010).
Nevertheless, an undocumented method that returns a JSON output is the following:
http://maps.google.com/maps/nav?q=from:London%20to:Dover
The format of the q
parameter should be from:xxx%20to:yyy
. Replace xxx and yyy with the start and destination respectively. You can use a latitude and a longitude instead of full addresses.
By default this request returns driving directions. To get walking directions you can add the optional parameter dirflg=w
to the query-string. (Source)
Note that not only this is undocumented, but it may also violate the restrictions 10.1 and 10.5 of the Google Maps API Terms and Conditions.
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