Hey guys,
I came across the Washington Dulles airport and noticed, there are plenty of roads tagged with access=destination. More or less everything except the main access roads for cars. As a result routers struggling to find a way from the airport to somewhere by bicycle (seems Valhalla is ignoring access=destination for bikes).
I checked the area with streetview and can’t find any sign leading to a access=destination, but I can understand somehow, the idea is to enforce, routers using the main access road. Not sure, whether the access should be changed to motor_vehicle or removed completely outside the parking areas?
For prohibiting through traffic within the airport area, as well as avoiding potential rules-breaking situation, based on sign Surli redirect page and discussion Slack
The tagging stems from a 1980s-era restriction intended to prevent commuters from doing an end-run around the Dulles Toll Road, which runs parallel to the Dulles Access Road. The restriction is signposted way over on the other end of the double freeway, and it is enforced. The Dulles Access Road is a very weird road, essentially an elongated, one-way freeway that serves only the airport with no intermediate exits.
@NE2 first tagged the freeway with access=destinationin 2012. Back in March, Lyft removed this tag, prompting a debate among local mappers. @YuliyaShustava_lyft started a discussion in OSMUS Slack, which reached the conclusion that access=destination should be applied to not only the freeway but also the surface streets within the airport area. Without these additional access restrictions, most routers would encourage motorists to evade the tolls. I had hoped that Lyft would take this discussion to a public venue such as this forum, in order to get everyone on the same page about this or perhaps other similar situations.
That makes sense to me, though then it should be better to use motor_vehicle=destination, as pedestrians and cyclist will are not part of this avoidance problem?
It might also be just an issue with OSRM and Graphhopper, as Valhalla and brouter seems to be able to find a way out.
Edit: brouter seems not to care access=destination at all based on the routing profiles. They only care about access=private|no, which would explain the routing.
I’m pretty sure cyclists aren’t allowed on the access road. As for the surface streets, all of the sidewalks have already been mapped as separate ways, and I’m unsure if bicycles are allowed on roads such as Saarinen Circle. Like most commercial airports across the country, Dulles isn’t designed to be accessible to cyclists. (It’s a miracle that it’s finally accessible by Metro after all these years.)
Would be the way to go. Though you can only get out, but can’t get in without using an emergency-access part only (like google suggest). And except the emergency-access part, there is nothing prohibiting the access for bikes.
Indeed, most American airports leaves that impression
Edit: Ok, now I found the sign and it seems to be, access=destination makes sense from the data perspective and routers need to learn how to handle the situation.
Though you can only get out, but can’t get in without using an emergency-access part only (like google suggest). And except the emergency-access part, there is nothing prohibiting the access for bikes.