Arendal is a town and a municipality in Agder county. The municipality of Arendal is often referred to as a large municipality after five municipalities, Arendal, Hisøy, Tromøy, Moland and Øyestad, were merged on 1 January 1992. The number of inhabitants in the municipality is 44,999 as of 1 January 2020.

Arendal is first mentioned as an important port in a customs account from 1528. In 1610, Peder Claussøn Friis says that Arendal was a charging station. There are many indications that Arendal is the oldest town on Agder. Arendal received full market town rights in 1723. The town of Arendal has 37,815 inhabitants as of 1 January 2020.

The municipality borders in the southwest towards Grimstad, in the northwest towards Froland, and in the northeast towards Tvedestrand. To the southeast, the municipality has a long coastline towards the Skagerrak.


Geography and nature
Arendal's topography is characterized by the coastline that runs in a direction from northeast to southwest. The landscape is dominated by fracture zones that partly run parallel to the coastline, partly north – south. The valleys in the fracture zones have steep slopes up to heaths located at about 100 masl. The highest peaks are Skrattereidknuten (222 m above sea level) which is the border between Arendal, Tvedestrand and Froland in the far northwest of the municipality, and Rindfjellet (254 m above sea level) southwest of the municipality.

The islands
Three large islands are located along Arendal's coastline, from west Hisøy and Tromøy separated by Galtesund, and furthest east Flosterøya. Outside and between these are a number of smaller islands: Outside Galtesund are Merdø and Torungene as well as Havsøya, outside Nedenes are Jerkholmen and Gjervoldsøy. Together, the islands in the municipality form a fantastic archipelago. Before the amalgamation of municipalities in 1992, the three large islands each formed their own municipality.

"Venice of the North" is a widely used characteristic of Arendal. One then thought of the old city center where, according to tradition, the buildings were erected on seven islets. Between the islets there were canals, as in Venice. "The city with the waterways" is the name of recent tourist brochures, and then one thinks of the many navigable leaders of the leisure fleet in sea or fresh water. The discussion is constantly about whether the city should dig up one or more of the refilled canals, and Kanalplassen is one of the city's gathering points. Canal Street is the city's jazz and blues festival.

Waterways and watercourses
The good harbor and the outlet for one of the country's largest rivers have created the city of Arendal. The harbor basin, which is often called "Byfjorden", is a closed and clean sea area and is surrounded by old buildings on all sides. From here, two straits lead out to the open sea, namely Tromøysund to the east, and Galtesund to the south.

From the west, the Nidelva, which is part of the Arendal watercourse, flows into the Byfjord. The Nidelva has two outlets, one on each side of Hisøy; inside the island, the river forms a small lake, Hølen. Smaller vessels can operate the river channel up to Helle, and they can go both river outlets south or west of Hisøy. Here also an idyllic tributary, Lillelv, flows into the Nidelva. It forms waterfalls that were previously exploited. The area around the Nidelva below Rygenefossen constituted Øyestad municipality. Around Rygenefossen, a small industrial site, Rygene, was established in the 19th century.

Further east in the municipality there are two smaller watercourses. The Barbu watercourse has a fairly small catchment area around Longumvannet and is drained through Barbuelva. This river has small waterfalls, and was important for business development in Arendal from the 16th century. The Molandsvassdraget begins with several small lakes and streams in the forests northernmost in the municipality. Molandsvannet is divided into several fjords separated by narrow straits. The watercourse is drained through the Sagene River, which has several waterfalls; here, too, there were upswing, milling and milling activities around the river. From Sagene there is a passable waterway through canals and water, Rånene, out to Neskilen by Tromøysund. The area around these two watercourses inside Tromøysund previously formed the municipalities of Austre Moland and Stokken.

Arendal has a coastal climate, with relatively mild and short winters, and moderately warm summers. The open sea, even in winter, means that the winter temperature is relatively high. The normal at Store Torungen lighthouse, measured from 1960 to 1990, shows that the coldest month is February with an average of −0.8 and the warmest month is July with 15.5; while October is usually the month with the most precipitation, 112 mm. April usually has at least 42 mm of precipitation.