Routes
sees both ends
start only
end only
neither
Drag any marker to try a nearby spot; every hop re-checks and the plan saves the new layout.
Relay candidates are bare-ground high points on a 250 m grid near the direct path, so ridgelines, towers and rooftops aren't considered, and the search stops at the fewest relays that work. Trees and buildings come from a 2011-2015 surface model. Treat every result as a lead to verify on site.