When travelling in Northern VA, I frequently travel east on I66 to the beltway I495 and then to Rt 50 towards Arlington. My GPS tells me to take the first exit (westbound) and circle back rather than just taking the eastbound exit. I don’t think it’s appreciably shorter. I think it may actually be longer! Anyone have any ideas why?
Microsoft Streets and Trips and Google Maps give the same weird circuitous directions btw.
thx!
Without looking, my first guess might be that the underlying map data may be missing the eastbound exit.
You mean from 495 to 50? It doesn’t happen when I do it on Google Maps.
The algorithms also weight the number of left turns versus right turns.
if I follow the GPS directions it’s all left turns to circle back around… the eastbound ramp is all right hand turn. Maybe enough people complained to Google that they fixed it. It’s weird though… the map displays the proper exit but perhaps that isn’t the underlying map but just a display. I dunno… makes me very distrustful of technology… no wait… I already was. this just confirms my suspicions!! 