This is not a mountain. It is a plateau above Grundarfjörður, cut away by ice. It is, in other words, a fall, or a fjall in Iceland.

Similarly with Kirkjufell below, just west of town. Not a mountain either.

However, the one below, in Berserkerjarhraun is a mountain. Fire has heaped it up. It mounts.
The one below at Glitstaðir is tricky. Neither mountain nor fjall, it’s a fell (Skálafell). Behind the farm it rises to 225 metres.

But this is just a glacier: langjökull, seen from Reykholt.

There just aren’t many mountains in Iceland. Lots of places where you can fall down, though.