Located at Piazza Castello, Turin's tourist info office is worth visiting to purchase the 2,3 or 5-day Torino+Piemonte Card. You can also purchase the city card in advance online (see the link below).

Turin is a city with lots of must-see palaces and museums, with admissions of 10-18 euros, 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 very reasonably priced so it's almost impossible not to save money with it.

Some of the sites you can visit for free with the card include the Royal Palace, Palazzo Madama, the Cinema Museum, the Egyptian Museum, the Lavazza Museum, and even the Venaria Palace, and that's just the tip of the iceberg.

If you reserve your spot on the official website of a museum/palace (most are linked on the corresponding spots on the map), you'll also see an admission option that says you have purchased the city card, which you'll have to show at the entrance.

I don't usually purchase city cards because I feel like most of them don't actually save you money - they either offer free entrance but are incredible pricey or are affordable yet only offer a tiny discount - but this one is a must in my eyes, and it saved me dozens of euros.

Alternatively, you can get the Royal Pass, valid for 4 days and offering FREE entrance solely to the palaces and castles of the House of Savoy in Turin and Piedmont (and the Basilica of Superga), as well as discounts on a few museums and public transport, but I think the Torino+Piemonte Card is more useful.