Außenalster or Outer Alster Lake is one of two artificial lakes within the city limits of Hamburg

Hamburg

-History:The first historic name for the city was, according to Claudius Ptolemy's reports, Treva.But the city takes its modern name, Hamburg, from the first permanent building on the site, a castle whose construction was ordered by the Emperor Charlemagne in AD 808...

, Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

, which are formed by the river Alster

Alster

The Alster is a right tributary of the River Elbe in Northern Germany. It has its source near Henstedt-Ulzburg, Schleswig-Holstein, flows roughly southwards and reaches the Elbe in Hamburg. In the centre of Hamburg the Alster has been dammed...

 (the other being the Binnenalster

Binnenalster

Binnenalster or Inner Alster Lake is one of two artificial lakes within the city limits of Hamburg, Germany, which are formed by the river Alster . The main annual festival is the Alstervergnügen.The lake has an area of ....

). The size of the Außenalster is 1.6 km².

The phrase "outer" refers to the old city walls of Hamburg. The Außenalster was the part of the lake that was "outside" the city walls. Today the old city walls do not exist, instead two car and train bridges, the Lombardbrücke and the Kennedybrücke, span the river.

The Außenalster is used by the inhabitants of Hamburg for recreation

Recreation

Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasure and are considered to be "fun"...

al purposes such as sailing

Sailing

Sailing is the propulsion of a vehicle and the control of its movement with large foils called sails. By changing the rigging, rudder, and sometimes the keel or centre board, a sailor manages the force of the wind on the sails in order to move the boat relative to its surrounding medium and...

 and rowing

Watercraft rowing

Watercraft rowing is the act of propelling a boat using the motion of oars in the water. The difference between paddling and rowing is that with rowing the oars have a mechanical connection with the boat whereas with paddling the paddles are hand-held with no mechanical connection.This article...

. Almost all banks of the Außenalster are public. The banks vary from a small strip of green to large public parks (e.g. the Alstervorland). It is very popular to jog around the lake (approx. 7 km).