The Sororium Tigillum, which translates as the "sister's beam", was a wooden beam said to have been erected in Ancient Rome

Ancient Rome

Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

 by the father of Publius Horatius, one of the three triplets Horatii

Horatii

According to Livy, the Horatii were male triplets from Rome. During a war between Rome and Alba Longa during the reign of Tullus Hostilius , it was agreed that settlement of the war would depend on the outcome of a battle between the Horatii and the Curiatii...

. Publius Horatius was required to pass under the beam, as if under a yoke, following the decision of the people's assembly not to punish him for the murder of his sister.

According to Livy

Livy

Titus Livius — known as Livy in English — was a Roman historian who wrote a monumental history of Rome and the Roman people. Ab Urbe Condita Libri, "Chapters from the Foundation of the City," covering the period from the earliest legends of Rome well before the traditional foundation in 753 BC...

, writing at the end of the 1st century BC, the Sororium Tigillum remained intact in Rome until his day, having been maintained at the public expense.