In the next few days both the Boston and the London marathons will be run. If you want to check out the routes and find a good place to spectate then you should check out these Google Maps.
Virgin London Marathon Interactive Map
This year Virgin have added some new features to their Google Map of the London Marathon. You can still see the route of the marathon and view Street Views along the route but there are also now some great guides to help you watch the race.
The map now includes a time slider option that allows you to see where the wheelchair racers, the elite male & females runners and the mass race should be at different times of the day. The mile markers also contain information about what kind of entertainment you are likely to find at different locations around the route.
Adidas: Boston Marathon in Street View
Adidas have produced a Google Maps app that lets you follow the whole of the Boston Marathon route in Street View.
The Boston Marathon Map lets you follow the route of the marathon using Google Maps Street View. You can navigate to points of interest on the marathon route and view an overlay on top of the Street View to enable you to jump forward to the next point of interest or go back to the previous POI.
The Boston Marathon app includes a Google Map of the route and a terrain chart.
Going the Distance - The Wall Street Journal
The Wall Street Journal's Going the Distance app includes Google Maps for the Boston Marathon, as well as the New York, San Francisco and Chicago marathons.
The map includes the route, an elevations chart and Street Views of the route. My favourite feature of the Wall Street Journals maps is the superb integration between the elevation chart and Street View. If you hover your mouse along the elevation chart the Street View will update to show the respective view. Very cool.