Tröllaskagi is such a hidden gem. Note, that there is a shortcut road between Sauðárkrókur and Blönduós, so going out of the ring road for the Tröllaskagi hidden gem, only adds 1 1/2 hour driving time of a superb scenic route.
What to do in Troll peninsula? All the places I mention here can be found on Google maps.
Langhus horse tours for a personal experience on horseback at a family farm icelandichorse.is.
Hauganes: Whales.is for absolutely outstanding whalewatching (the best whalewatching tours in Iceland, in my experience), and Baccalá restaurant and the beach pots. The Beer baths.
Mígandifoss waterfall.
Ólafsfjörður village.
Fairytale at sea.
Segull brewery.
Siglufjörður is so beautiful, with it’s colorful houses, strikingly beautiful harbour, and good restaurants. The Herring museum is one of a kind history time capsule.
Sóti summit has various fun tours.
The strikingly beautiful road around the whole peninsula is one scenic tour.
Brúnastaðir farm zoo and Farm produce shop.
Sólgarðar hot tub/sauna/pool.
Stífluvatn is a gem, but just for June-September, at other times the road can be closed (impassable).
Hofsós for the Infinity pool, Retro restaurant and Staðarbjargavík basalt columns.
Gröf turf church.
https://www.drangey.net/ for the best puffin and more birdwatching experience in Iceland.
The black beach of Sauðárkrókur.
