Dogs are allowed on Geldinganes without a leash (under supervision). Should this be mapped and tagged as leisure=dog_park?
Sources:
http://reykjavik.is/sites/default/files/skjol_thjonustulysingar/hundasam_ykkt2012.pdf
and
http://borgarvefsja.reykjavik.is/borgarvefsja/#
(See "Þjónusta > Hundasvæði - lausaganga hunda".)