Yep, a shark museum.
Fermented shark meat is a delicacy in Iceland, used for special celebrations (and for scaring tourists).
I'd tried shark meat before, and wasn't especially enamoured - but my boyfriend is a big fan, so I took one for the team.
The museum is basically a small warehouse filled with greenland shark memorabilia. The family that runs it have been shark-hunters for generations.
You can see some of the tools used to catch the greenland sharks, and some cool bits of shark anatomy, including a shark's jaw, complete with conveyer-belt-like sets of self-replenishing teeth.
After looking at the bits and bobs, we were shown a short video on the history of Iceland's sharking industry, and how they catch and prepare sharks, until we were finally able to sample the delicacy itself.
An indescribable taste, but certainly a lot better than the shark we'd tried in a restaurant in 2015.
We also got to visit the drying shed where the shark meat is left to putrefy. Pungent stuff.
Overall, although it was an interesting experience, I don't think this is worth the ISK 2200 entry fee.
...Plus, everything smelt of wee (as with all cartilaginous fish, when the meat decomposes, it gives out ammonia-rich urea. In fact, it's toxic to eat unless prepared in this specific way).