If you take the sea route north you have several options. The various routes have been dealt with in history, and through the Middle Ages the traffic increased as well as the trading with Nordland in fish and herring, feather and down. One of the central routes passes through Kjelstraumen, in the sound between Ulvøy and Bakkøy. This has been a place for a guesthouse since 1610, with Royal Letter of Privilege, part of the large network of trading post and guesthouse locations along the coast.
A marsh is a grassy meadow that is strongly influenced by salt from the sea. This type of nature is abundant in Denmark, among other places. The flatlands along the river that run out by Leirvågen, are the municipalities' largest marsh. At spring tide, these flatlands are flooded underwater for several hundred metres in over land.
Lake Purkebolsvatnet is perhaps western Norway's largest sleeping city - for birds. They come in the thousands, usually in later summer and autumn. The barn swallows alone number 10 000 - 12 000 at their most numerous.