The ancient Roman deity of locks, gates, animals, and ports was known as Portunus.
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He could have first guarded grain storage facilities, but eventually came to be connected with ports, either as a result of folk links between porta, the word for entrance or gate, and portus, the word for harbor and the “gateway” to the sea, or due to an extension of the meaning of portus. Later, Portunus and the Greek name Palaemon were combined.
Given that he shares many traits, roles, and the key’s symbol with the deity Janus, Portunus looks to be linked to the latter. On coinage and as the figurehead of ships, he was also shown as a two-headed creature with the heads pointing in different directions. As “deus portuum portarumque praeses,” he was revered (lit. God presiding over ports and gates.) The fact that Emperor Tiberius selected August 17—the day of the Portunalia—to dedicate the restored Temple of Janus in the Forum Holitorium highlights the connection between the two deities.
The Portunalia was Portunus’ festival, which was observed on August 17, the sixteenth day before the Kalends of September. On this day, keys were ceremoniously and lugubriously tossed into a fire for good luck. His symbol was a key, and the Temple of Portunus, his principal temple in Rome, could be located in the Forum Boarium.
Featured image: Temple of Portunus, Rome

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