[Tagging] start_date variants

[Richard]

On Fri, Feb 15, 2019 at 11:03:01AM +0100, Stephan Bösch-Plepelits wrote:
> Hi!
> 
> I have some thoughts in the start_date tag, as I find it a bit too vague -
> meaning start of what?
> 
> Example: There is this museum, which openened in 2011, but the building is
> much older, it was built in 1725: https://www.openstreetmap.org/relation/1937535
> 
> An option would be to prefix start_date with the key of the indicating tag,
> e.g. amenity:start_date would describe the start_date of the current
> amenity. So, non-prefixed start_date would apply to all other tags.

exactly.


> This seems to be quite popular anyway, but I don't know if this ever has
> been agreed upon - at least it's not documented as such:
> https://taginfo.openstreetmap.org/search?q=start_date
> 
> For the museum, which I mentioned before, I used the following tags:
> - start_date=2011
> - building:start_date=1725

another variant has been documented:
https://wiki.openstreetmap.org/wiki/Proposed_features/Date_namespace

> 
> Other remarks:
> 
> It would also be interesting to be able to tag the start of construction -
> often construction starts many years before the building is finshed:
> Airport BER in Berlin, Germany or La Sagrada Familia in Barcelona, Spain
> are famous examples. How to tag this? Maybe: construction:start_date?
> 
> Any thougths on this?

you could map what was there at any particular time but I think it is better
to provide the link to wikipedia. Ordinary users will ever look at OSM data
close enough to find out this details.

Richard