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What are exit numbers?

  • An exit number is a number assigned to a road junction, as an exit from a freeway. It is usually marked on the same sign as the destinations of the exit.

Different tags for exit numbers:

  • ref=* is used when the exit has a specific number assigned to it.

How to add exit numbers?

  • Use the Tasking manager link in the mapping ticket.

    germany1

    When we lock a motorway in Tasking manager, a link appears to take us directly to the road in Checkautopista2

Verify the exits on the route for missing information

  • Editing in JOSM

    germany2

Loading from Checkautopista2 to JOSM

screen shot 2016-04-05 at 6 47 15 pm

These are the colour representations for the exits detected in Checkautopista2

  • Browse along the route and check the ways on both directions at every Exit location for the following:
  • There is a motorway_junction in the starting node of the motorway_link exiting the highway red dot
  • The motorway_junction has a correct exit number ref value as per the source. Nodes with missing ref tags represented by a blue dot
  • The exit number on both directions are the same.
  • There is only one exit in a direction for every exit number.

Add missing exit numbers

  • Download the data and mapillary layer to locate a signboard around the blue marker in the imagery.

  • Use a combination of Mapillary, to add the ref=* tag on highway=motorway_junction (stick to using Mapillary as primary source and move to others in case of unavailablity of information)

Analyzing signboards in mapillary

Look out of highway sign boards in the satellite imagery. They may look something like this-

screen shot 2016-08-31 at 2 32 47 pm

Places to look for-

  • near a motorway_junction

  • near start of a motorway_link

    screen_shot_2016-08-31_at_2_49_26_pm 2

Do's and don'ts

  • It is not necessary that exit numbers are sequential. It might be 45 after 41.

  • There are some motorway_junction which don't have any associated exit number. Add noref=yes on these nodes. screen shot 2016-08-31 at 3 03 53 pm

  • If there are multiple exits on the same signboard then you can tag them as ref=* ; * instead of ref:left=* and ref:right=* until you are confirmed with that.

  • Ignore the highway=motorway_junction where the traffic flow is towards the motorway

What are destination tags?

  • Destination tags (destination=*) describes where a certain exit leads to.

    screen shot 2016-09-08 at 12 19 19 pm

Different tags for destinations:

  • destination - placename that the way exiting from the freeway leads to.
  • destination:ref - reference of the roads directly ahead.
  • destination:street - streetname the way exiting from the freeway leads to.

How to add destination tags?

  1. Look out for red outer circle in Checkautopista for missing destination. Use Open in JOSM button to open the node in JOSM. Orange outer circle represents exit_to tag and we don't need to add destination tags in the way. Green outer circle represent that the concern way already has destination tag.

germany2

screen shot 2016-04-05 at 6 47 15 pm

  1. Download the data around the motorway_junction and mapillary layer to locate a signboard.

  2. Use combination Mapillary images and Exit explorer to add destination as destination=* on motorway_link ways and the destination highway as destination:ref=*.

Below is a an example screen_shot_2016-08-31_at_3_14_14_pm

Do's and don'ts

  • Use ; to separate multiple destination and refs.
  • Read more on Highway intesection to understand them better.
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