The Buen Retiro Park in the center of Madrid is one of the largest parks in Madrid and belonged to the Spanish Monarchy from about 1505 until the late 19th century when it became a public park. map
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The Great Pond was created in the 1630s along with much of the park layout.
This Monument to King Alfonso XII was designed by architect José Grases Riera in 1902 and was completed and inaugurated on June 6, 1922.
In the center is the bronze equestrian statue of King Alfonso XII, then three statues representing Peace, Freedom and Progress. Below them at the top of the steps are four stone lions, and at the bottom of the steps on the water's edge are four bronze mermaids.
One of the mermaids, by Antonio Alsina y Amils, sits on a turtle, playing music on a lyre.
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The next, by Rafael Atché, sits on a large fish while listening to the sound in a conch shell.
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The third mermaid, by Antonio Parera Saurina, appears to be battling a giant lobster while wielding a staff with a spiky conch at one end.
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The last of the mermaids, by Antonio Coll y Pi, is relaxing on a fish while brushing her hair out of the way with her right hand.
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The park and especially the pond are extremely popular with locals and tourists, and most days the lake is filled with people in many small boats slowly sailing about.
References:
● The Mermaids of Earth coffee-table book: See page 84 in the book about this sculpture.