[OSM-talk] When is a road a secondary road and when is it not?

[Kev]

>  I can't always tell the difference when a Trunk and a
> Primary I know of Primary that could be retagged as Trunk as they are
> great big dual carriage ways with slip roads etc eg A289 to Hoo.
>   
Both Primary and Trunk get green signs - but only the latter are 
maintained by The Highway's Agency (in England) or on behalf of - the 
rest are local authority roads - some local authority roads (i.e. 
Primary) often have multiple lanes and central reservations, yet parts 
of the remote trunk road network are single track with passing places!

Not aware of any full list of these that is okay to use in OSM, but 
signs like  "A50 Maintained by Connect Roads on Behalf of the Highways 
Agency" give this away, as does looking at signs through roadworks.

> There seams to be a long list of roads tagged as Motorways without
> numbers
Some short sections don't have signs - is the Walton Summit Motorway 
http://pathetic.org.uk/secretive/walton_summit_motorway/ a motorway or 
glorfied sliproad - then there is the A635(M) - Signed on the ground as 
Motorway (i.e. under motorway regs) but without a number until the A57 
joins at the otherside of the junction to become A57(M).