Example route – The direct north-to-south road between the starting and ending points doesn’t actually exist. It’s tagged with “construction:highway”, so I would have expected that it would be omitted from routing consideration…
GraphHopper supports the (more popular) tagging
highway=construction, which is used 285714 times according to taginfo. In this case the road is tagged as
highway=tertiary;construction=highway which is not supported by GraphHopper and only used 938 times according to taginfo.
Also see this (old) discussion: GH doesn't respect construction tag? · Issue #375 · graphhopper/graphhopper · GitHub
“highway=construction” sure seems to make a lot more sense. I’ll fix it. Thanks!