Import the spiral route from ridewithgps, by pasting in the target of the kml link on the ridewithgps export tab
Done
The new map in My Places should have a KML link, if it doesn't adding a comment to your map sometimes makes it appear
Copy and paste the target of the google maps KML link into the google maps search box and click - this allows you to view the whole thing on one screen.
This is the only way I've found to see the route against a map of the borough boundaries, does anyone know a better way ?
In google maps: