Located at Piazza Castello, Turin's tourist info office is worth visiting to purchase the 2,3 or 5-day Torino+Piemonte Card. Turin is a city with lots of must-see palaces and museums, with admissions of 10-18, and this city card lets you visit most of them for free and gives discounts on other attractions, tours, and multi-day public transport tickets. It also includes free entrance or discounts on landmarks in the entire region of Piedmont, and it is reasonably priced so it's almost impossible not to save money with it. You can also purchase the city card in advance online. If you reserve your spot on the official website of a museum/palace, you'll also see an admission option that says you have purchased the city card, which you'll have to show at the entrance.