Traismauer is a municipality with 6224 inhabitants (as of 1 January 2018) in the district of Sankt Pölten-Land in Lower Austria.
Traismauer is located in the lowest Traisental in Lower Austria. The area of the municipality covers 43.14 square kilometers, 28.14 percent are wooded. In antiquity, the area was part of the province of Noricum and site of the Augustinian horse stable. Documented Traismauer was first mentioned in 799 as Tresma. After the conquest of the Avars empire by Emperor Charlemagne, the place in the new East Bavarian land was the seat of the Count Cadaloc, who fell during the last battles against the Avars in 802 at the Castell Guntio. Count Cadaloc was buried in the church of St. Ruprecht in Traismauer.