面積160公頃、周長7.6公里、湖最深處只有2.5公尺的阿爾斯特湖 (Alster Lake)，是一個自13世紀起由易北河的一條支流—阿爾斯特河 (Alster River, 25 km north of Hamburg and only 56 km long)，在漢堡市中心被人工阻截而建的湖泊。 整個湖泊由倫巴第橋 (Lombardsbrücke ) 和甘迺迪橋 (Kennedybrücke) 為界，區分為內阿爾斯特湖 (Binnenalster) 和外阿爾斯特湖 (Außenalster)。 內阿斯特湖被漢堡市中心，最古老，也最有代表性的建築群所包圍：周圍有著名的百貨公司、飯店、銀行以及世界名牌店等等。而外阿爾斯特湖的周邊環境則十分優美，被大片的綠樹和草坪所環繞，許多豪華的別墅、住宅區依湖而建，是漢堡居民進行散步、烤肉、駕駛帆船等休閒活動的場所。
p.s. The Lombardsbrücke (front) is a road and rail bridge over the river Alster in Hamburg. It was named after the Lombard pawn shop situated here in 1651. The original wooden bridge was replaced in 1865 by the now 69-meter long bridge that spans the river Alster in three arches between Inner and Outer Alster. Next to the Lombardsbrücke is the Kennedy Bridge(back). It was constructed in 1953 because the old Lombardsbrücke couldn’t cope with the increased traffic. The bridge was originally called New Lombardsbrücke. It was renamed Kennedy Bridge in 1963 in honor of John F. Kennedy after his assassination.
Tour the Alster Lake by the solar vessel—Alstersonne：
Begin from Alster Pier at Jungfernstieg, we are going have lunch on the vessel while touring the Alster Lake.
Tour the Binnenalster by foot：
p.s. Hamburg’s particular liking of the Alster swans has not only a long tradition, but also a certain importance for the hanseatic town. The city fathers in the old days thought, as long as there are swans swimming on the Alster, Hamburg would remain a hanseatic town.
Already at the end of the 16th century, the city provided barley and oats for the swans. Since 1818, a special swan keeper is responsible for them. He looks after their food and takes care of the injured ones. In winter, he takes them to a smaller pond, which is kept ice-free for them.