He is mainly known for his investigations of Swiss lake dwellings in 1853–54,[1] and work on the remains of the La Tène culture.

In 1831 he was made an instructor at Zurich, and secretary of the Society for Natural Research, and in this capacity he published various works on naked rock soil and vent holes.

In 1857 a skeleton wearing bronze jewelry was unearthed near Robenhausen, and Jakob Messikommer who later discovered and researched the Wetzikon-Robenhausen settlement, reported the findings to Keller.

[3] The American Philosophical Society elected Keller an international member in 1863.

He also published Bauriss des Klosters Sankt Gallen vom Jahr 820 (1844), and an archaeological map of Eastern Switzerland (1874).