How Do You Spend Time Before an Evening Flight?

Hotel checkout is often in the morning, while the flight leaves much later in the evening. This leaves several hours that can be used for sightseeing or a relaxed walk around the city. I recently started using https://todoway.com/ to organize this time. I add the places I want to visit, arrange them into a route and check how much time the whole plan takes. It helps me see what I can fit into the day before heading to the airport. How do you usually spend these extra hours? Do you visit a few attractions, walk around the city or simply head to the airport early?