New this week Factual error: The party in honour of Gianna, Santino's sister, is held at the Terme di Caracalla (Baths of Caracalla). That site belongs to the city of Rome, and would never be used to host a private party, let alone a party in honour of a major Mob figure. Moreover, the place where John and Gianna meet while she's about to take a bath is the Horti Sallustiani (Gardens of Sallust), which are some 5 km away from the place where the concert is being held.
Factual error: After John Wick's house blows up, he takes his dog for a long walk into the Continental in Manhattan. He lives in New Jersey and walks into Manhattan over the Brooklyn Bridge which is on the complete other side of Manhattan, crossing over into Brooklyn and not New Jersey.