Some cruise ships do stopover either in the San Blas Islands in the Caribbean or at the pier in Balboa near both Panama City and the Pacific end of the Canal. If you have a day in Panama and want to have a budget getaway, a trip to the Isle of Taboga about 12 miles from the capital city might be just what you need. Ferries leave Muelle (pier) 18 at the port of Balboa (near the cruise ship pier) three or four times a day, starting at about 8:30 am. The boat makes the hour trip to Taboga for about $10 round trip. (Panama uses American paper currency--no exchange necessary.) This is a real bargain! With your ticket, you get to cruise under the Bridge of the Americas and out the Pacific Ocean side of the Canal. On the way you get great views of Panama City on the other side of the causeway. In addition, you can get a close look at the many ships queued up waiting their turn to transit the Canal.
Taboga is a popular day trip from Panama City, so the boat may be crowded, especially on the weekends. I'll never forget one trip we made on a beautiful Saturday. The ferry was crowded, the music was loud, and everyone was dancing and enjoying their day off. I was with my co-workers, and we were about the only Americans on board. The locals encouraged us to join in the fun, and we had a great time during our hour-long boat ride.
When you arrive on Taboga, you probably will want to purchase a ticket to use the beach and facilities of the Taboga Beach Resort. This costs a nominal fee, but includes lunch and use of the bathrooms and changing rooms, etc. You can also stay overnight at the 60-room hotel if you have the time. The resort is not deluxe, but the pool, beach and restaurant are okay and the view of the ocean traffic is marvelous.
Before you settle on the beach, you should explore the island. It won't take you long to see the "city"! The island is about 2.3 square miles (5.9 square kilometers). There is one small street, and a few paths. The "main street" takes you by a couple of open air bars, and gives you a chance to see how Taboga has earned its name, the island of flowers.
You might have an opportunity to meet some interesting people in these open air bars. Taboga is a popular port of call for sailboats waiting to transit the Canal. An American struck up a conversation with us in the Hotel Chu Bar when he heard our accents. He had left California a few months before and had sailed down the coast of Mexico and Central America, stopping along the way. He was anxious to hear "news from home", and we spent some time talking with him. He told us some great stories of storms he had sailed through and life at sea.
There are some fascinating homes, an interesting old cemetery, and the beach at the hotel is relatively clean and restful. You can walk the main street in about 10 minutes if you don't stop. If you feel energetic, you can wander the network of well maintained paths around the island, many of which are lined with a variety of orchids and other flowers. Depending on the time of year, you might see thousands of pelicans nesting on the back side of the island from the boat dock. It will take you about three or four hours to explore the island.
While touring the island, you can think about the historical role this small island has played. One of the first settlers in the 16th century was Padre Hernando de Luque, dean of the Panama cathedral. He built a comfortable house on the island, and stayed there much of the time. Padre Luque is famous because he was the financier and mentor of Francisco Pizarro, conqueror of the Incas. Pizarro also had a house on Taboga, the remains of which are still on the island.
Taboga served as an important port for the North American and English fleets at the beginning of the twentieth century. It has also been a source of respite from the heat of the city and from epidemics. For such a small island, its past is quite flavorful. Now, most people enjoy swimming a little, sitting in the shade (or the sun), and savoring the peaceful beach and the Gulf of Panama in the Pacific Ocean.

