Even after players reach act three of Baldur's Gate 3, they have a ways to go before they can enter the city itself. Fortunately, there is entertainment aplenty in the outskirts, in particular the Circus of the Last Days by the Open Hand Temple.
Baldur's Gate 3: Guide to the Circus of the Last Days
One reward for reaching act 3 in Baldur's Gate 3 is access to the Circus of the Last Days, a fully optional but fascinating location.