Giotto's Bell Tower, it's the bell tower of the Cathedral of Santa Maria del Fiore in Florence. It's always been one of my favourite places in Florence and have loved to go to the top to see the stunning view it offers. To climb to the top it's a challenging 414 steps, however, the view is very rewarding. Compared to the view from Dome of the Cathedral, I loved the view from Giotto's Bell Tower as you can actually see the masterpiece of the Dome of Brunelleschi.
If you get the chance to visit both the Dome and the Bell Towers viewpoints, I'd recommend doing it on two different days. The last time I visited Florence I did them both in a two-hour span, and I was exhausted, as also the Dome has over 400 steps to climb.
To visit the Bell Tower, this is the ticket I recommend: The Brunelleschi Pass. Adult ticket costs €30 and includes the visit to the Cathedral, Giotto's Bell Tower, the Baptistery, Duomo Museum, Santa Reparata and Brunelleschi's Dome. The ticket is valid for 3 days from the date selected.
There is also a ticket for the Bell Tower alone, which is Giotto Pass which costs €20.
Make sure to always book your tickets from the official website, to not risk getting scammed or pay extra. I put the link of the official website here