Eldheimar Museum stands on the site where lava deposits were uncovered following the 1973 eruption on Heimaey Island. The building itself covers one house that was completely buried under lava, and another house, which is only partially uncovered, is situated near the museum entrance. The second floor of the museum is dedicated to Surtsey Island, which remains the youngest island in the world to this day (formed at the end of 1963 during an underwater volcanic eruption).
The museum is exceptionally well-designed, and if you are on the island, it is one of the must-visit places. I would even go as far as to say that if you are in Iceland and interested in more than just viewing waterfalls, you should consider visiting Heimaey Island specifically for this museum. You can easily spend several hours exploring the exhibits.
You can find the Eldheimar Museum on the outskirts of town, right beneath the Eldfell crater. It’s about a 25-minute walk from the harbor to the museum.