Short walking trails lead from the museum area uphill to waterfalls, and to the 'sound sculpture' Tvísöngur – five interconnected concrete domes. Another short walk leads from the road on the north shore of the fjord (about 6km beyond the Bláa Kirkjan) to the signposted Dvergasteinn (Dwarf Rock) – according to folklore, this is a dwarf church that followed the people's church across the fjord.
The hills above Seyðisfjörður are the perfect spot for longer hiking. Vestdalur is a grassy valley north of town renowned for its glorious waterfalls. The hike begins just before the Langahlið cottages. Following the Vestdalsá river, after two to three scenic hours you'll arrive at a small lake, Vestdalsvatn, which remains frozen most of the year (it's generally covered by snow until July).
Trails are marked on the widely available Borgarfjörður Eystri & Víknaslóðir Hiking Map – Trails of the Deserted Inlets map (1000kr), and the www.visitseydisfjordur.com website outlines some options, including the Seven Peaks Hike (trails climbing seven of the 1000m-plus peaks surrounding the town).