Click on the map to place markers. Click on markers to show coordinates. Double click on markers to remove them.
If the distance between the 2 markers is smaller than 102 Km, the graph will show the elevation every 200 m.
If the distance is larger than 102 Km, the graph will show the elevation of 510 points spread evenly between the markers.
This is the current limitation of the elevation service from Google Maps Api v3.