The famous Maria Theresa Square (Maria-Theresien-Platz) in Vienna is home to four fountains with tritons and nereids, of which one clearly includes a twin-tailed mermaid. map
The fountains are each at the center of one of the four rectangular garden areas that define the square.
This fountain depicts a Triton portrayed as an elderly man (with feet) on a conch shell being offered a strand of pearls by a twin-tailed mermaid. Created in Carrara marble by Austrian sculptor Anton Schmidgruber, it was unveiled in 1894.
All four fountains are referred to as Triton and Naiad fountains. In this fountain the female figure is the naiad (mermaid), whereas in the other three fountains the male figures are tritons (mermen with tails) and the female figures have human feet.
● The Mermaids of Earth coffee-table book: See page 64 in the book about this sculpture.