I would 10000% recommend to do a free walking tour in Cusco. The city has SO MUCH amazing history and unique facts that I found fascinating. There are loads of different tour companies to choose from and they all offer the same rough itinerary. You could sign up in advance online or just show up to the Plaza de Armas and join a tour.

Of course, every free walking tour isn't technically free since you need to tip the guide at the end. Our tour even included a free Pisco Sour so I think its very worth it. Cusco has many winding alley ways so it's easy to accidentally skip entire neighbourhoods. The walking tour gave me a great overview of the city so I could better explore it further on my own time.