The rivalry with Oca:
That between Oca and Torre is the only rivalry between non-neighboring Contrade and is certainly the most heated and felt.
Establishing the reasons for such enmity is not easy: arguments allegedly due to divergent economic interests degenerated giving rise to the first grudges, which then consolidated in a mutual struggle for city supremacy.
The Palio has certainly contributed to cementing the enmity with its thousand events, made of spite and betrayal. Already in the nineteenth century the two Contradas competed on every occasion for the Gobbo Saragiolo (aka Francesco Santini), a mythical jockey, at the time the authentic king of the Piazza: he, indifferent to enmity and faithful to mercenary ethics, won three times for Oca and five times for Torre. Although over the years there have been various attempts to reconcile (the last dating back to the early twentieth century), enmity has never returned. Its irreducibility has meant that the contractors currently feel this rivalry much more than that of a much older one with Onda.
The unofficial rivalry with the Torre:
The rivalry between Onda and Torre is probably the oldest among those currently existing, being born around 1559.
It is certainly the most convulsive, given that relations between the two Contradas have always been fluctuating: from the bloody seventeenth-century clashes, which even provoked victims, long periods of respite and real alliance came.
But the rivalry exploded following the events of the Palio of 3 July 1930: at the time Onda and Torre were allies and their excellent relations, especially after the Contrada of Malborghetto had moved away from Oca, following some misunderstandings over the years twenty. On that occasion, Torre, having received the fast puppet, was counting on breaking a twenty-year fast and asked for the support of the ally. But Onda, despite having won just two years before, did not want to give up a probable success, thanks above all to the fact that the mare received by lot, Lina, was one of the best subjects of the lot.
Oca took advantage of the situation and, to avoid the victory of the hated Torre, proposed to Onda to exchange the jockeys. Onda accepted willingly, so the deflated went with the jacket of Fontebranda, from which came the noble Picino. Torre felt so betrayed by Onda and a spark was enough during a test to create very hard clashes between the peoples of the two Contrade. The tension remained high even after Onda victory in that career: since then Torre has been the official rival of Onda.
According to other testimonies, the relationship between Onda and Torre deteriorated even more due to the very tense relationships between important families of the two Contrade. However, this rivalry has never been made official by either Contrade.
From: Wikipedia, l'enciclopedia libera.