Editing Mälaren (section)

== Mapping ==
From the mid 17th century onwards, multiple expeditions to measure and map L. Mälaren were undertaken. The lake was strategically and economically important, and there was a lack of a reliable map to navigate it. However, L. Mälaren’s many islands and bays made it an extensive and laborious task to measure.

In 1687, [[Charles XI of Sweden|King Charles XI of Sweden]] commissioned cartographer [[Carl Gripenhielm]] to map Lake Mälaren and its surrounding provinces.<ref>{{Cite book |last=Landell |first=Nils-Erik |url=https://www.worldcat.org/oclc/165391840 |title=Stockholmskartor |date=1992 |publisher=Rabén & Sjögren |isbn=91-29-61681-6 |location=[Stockholm] |oclc=165391840}}</ref> From 2 August 1688 to 17 September 1688 Gripenhielm conducted the bulk of his expedition, and he would complete the map in 1689, known in Swedish as [[Gripenhielm's Mälarkarta|Gripenhielm's ''Mälarkarta'']]. The Mälarkarta is unique in that it is surrounded by a frame of 96 small, realistic gouache paintings of cities, castles, mansions, and fairways around Lake Mälaren. The map is hand drawn on regal paper, and measures {{cvt|3.46 x 2.14|m}}. It has been kept in the [[National Library of Sweden]] since 1884. Due to its larger size, it was initially hung in the large viewing room, however in 1931 it was moved to a more secluded wall in a corridor to the map department. Heavy handed preservation techniques have led to some degradation on the illustrations. Since 1961, the map hangs in an area that the public does not have access to.

Gripenheim’s Mälarkarta was valid until 1739 when a new, more accurate map of L. Mälaren was completed by the then surveyor and cartographer [[Jacob Nordencreutz]].