Temple of Mercury

building, Baiae, Italy

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July 16, 2026

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The structure referred to as the "Temple of Mercury" in Baiae, Italy, is not a temple but rather a large, domed building that served as a swimming pool for a bath complex. This structure dates back to the late Roman Republic. Baiae itself was a popular resort town during the later Roman Republic and into the 1st century CE, known for its mild climate and curative thermal springs. The town experienced significant development with the construction of numerous villas, including those belonging to prominent figures like Julius Caesar and Nero. Emperor Hadrian also died in a villa in Baiae. Due to volcanic activity, a portion of the ancient site is now submerged in the bay.1

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Baiae
The “Temple of Mercury” (about 71 feet [21.5 metres] in diameter) dates from the late Republic. Reminiscent in its present condition of the Pantheon, it was the swimming pool of a large bath. The “temples” of Venus and Diana are of the Hadrianic period (2nd century…
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The “Temple of Mercury” (about 71 feet [21.5 metres] in diameter) dates from the late Republic. Reminiscent in its present condition of the Pantheon, it was the swimming pool of a large bath. The “temples” of Venus and Diana are of the Hadrianic period (2nd century…
Read More