If you don't have time to go visit the Panama Canal, there is a museum right in Casco Viejo. You can learn about the history of Panama and its canal through its permanent collection and temporary exhibitions of art, culture, archeology and photography.
Enjoy beautiful views of Panama on your way to Flamenco Island where you can eat on the water or even take a ferry. Leños & Carbon Amador restaurant comes highly recommended.
Nomé Chocolate is a high end artisanal chocolate boutique and factory located in Casco Viejo. You can take a class to learn about the cacao and the technique required to process, dry and roast its pods to make chocolate.
Visit the oldest cafe in the city, and one of the first places where Coca-Cola was sold outside the United States.
An iconic street in Casco Viejo (pictured above).