[Tagging] How to start?

[M∡rtin Koppenhoefer]

I also found recently information attached to a bridge (in a more
technical and less representative way), actually a really small
pedestrian bridge:
http://www.23hq.com/dieterdreist/photo/5953091
http://www.23hq.com/dieterdreist/photo/5953084

Sorry that they are hard to read due to reallife tagging ;-)

is there anyone already tagging these? If you use ref for these
number, how would you distinct them from ref on the street? Maybe I
should use ref:bridge for them?

cheers,
Martin