There are two quite similar sculptures with each two mermaids in Bologna's Montagnola Park. This is near the center of the city, and is in the city's oldest park. map
The mermaid sculptures were created in 1888 by local artist Diego Sarti, famous for many works of art. These were created in concrete for the 1888 National Art Exhibition, and although they were supposed to be dismantled after the exhibition, popular acclaim resulted in them being preserved as part of the city's history.
● The Mermaids of Earth coffee-table book: See page 69 in the book about this sculpture.