Hafnarfjörður town belongs to the so-called "Great-Reykjavík area" and I have made a special page on Hafnarfjörður with tips on what to do there. It is a lovely town built on and around big lava rocks.
Hafnarfjörður is built around the harbour which was once one of the main harbours in Iceland.
The Viking village is located in Hafnarfjörður and has a really interesting Viking restaurant and bar and the Hotel Viking. The decor is Viking style and the atmosphere is pure "Viking". The waitresses are dressed up as Valkyries and the menu consists of "Viking food".
Hafnarfjörður hosts the Annual International Viking Festival which will be held for the 14th time this year (2010). Thousands of "Vikings" from all over the world (mostly Scandinavia, England and Germany plus Icelanders of course) gather in and around The Viking Village and the fun goes on for several days (see my tips on my Hafnarfjörður page). Do pay it a visit if you are in this area in June. Iceland is called the Mekka of Vikings :)
Bjarni Sívertsen 1763-1833 (my ancestor) was a pioneer in Icelandic shipping and trade and a great entrepreneur in Hafnarfjörður from 1794-1830 and owned a fishing business and a shipyard there. He was one of the best known traders in Iceland. He received The Knight's cross from the Danish king and was always called Bjarni riddari Sívertsen from then on (Sir Bjarni). He has been named The Father of Hafnarfjörður for his part in saving the town from ruins and for making it into a blossoming town. Part of his former home hosts the Hafnarfjörður District Museum. His home, The Sívertsen House in Vesturgata 6, is the oldest house in Hafnarfjörður, built in 1803-1805 by Bjarni Sívertsen himself.
There are 2 prominent parks in Hafnarfjörður, the small and lovely Hellisgerði, where the statue of Bjarni Sívertsen is situated, and Víðistaðatún park, which is a big park with a pond.
Hafnarfjörður is well worth a visit while visiting Reykjavík.
Hafnarfjördur is about 15 minutes by car from Reykjavik. In Iceland you have a lot of legends involving elves, dwarves and trolls. For me this is unsurprising in regard of the mystical landscape :). It is said, that in Hafnarfjördur a very large population of those hidden people is to be found. But also apart from the elves, dwarves and trolls, Hafnarfjördur is a nice little town with an interesting harbour. Whale watching tours are departing from there too. I saw some nice walks on the cliffs, unfortunately it was too windy to get out of the car, I feared to get blown away. The odd looking Viking village restaurant is located in Hafnarfjördur too.