Added some tags. Hope that the tag informal=yes, can be used to make it easier for the community and public officials to learn about and thus respect or take into account more or less established usages of land.

The sled piste, and grass area Solheimabrekkan added

Added a small slope where children like to use sleds or skis in winter. In summer it is a meadow / grassland

Make dog-pen more visible. Call it a recreational area.

Footway , path under construction

Added bicycle=yes to help routing

These pieces of shared, multiuse path have been paved for a few years now

Connect designated cycle path through tunnel

New short designated cyclepath. Joined to path through "park" in Fossvogsdalur by shared cycleway ( with sharrows / bike and chevron ) in Traðarland "residential street".

Added newly completed designated pedestrian path through the small forest. Removed tags for portion of bicycle path, that seems to have been turfed over.

Changed name to distinguish from the name of the small forest area that the path goes through, Svartiskógur. Added tag to show the designated cyclepath is bidirectional.

The footway or multi-use path is proposed rather than under construction

Added some rough outlines of most visible buildings of the RioTinto Alcan Aluminum plant

Planned path Added tag highway = construction

Planned path Will extend in next edits

Bicyclke route has been moved to short new path through the woods

Connect segregated cycle path to road, residential, with sharrows / bike-and-chevron markings

Segregated cycle / bicycle path, Fossvogsstígur, updated

New cycle / bicycle path, segregated. Segregated pedestrian path built at the same time along side. News on the path on the Reykjavik City website (in Icelandic) http://www.reykjavik.is/desktopdefault.aspx/tabid-757/521_read-36664

Connecting stubs to make crossing from paths / pavement routable