If you want to relax, there’s the Amador Causeway. This two mile causeway connects collection of four small islands, Naos, Culebra, Perico, and Flamenco, to the mainland. The islands were once part of the Panama Canal Zone and used for the defense of the canal during WWII. The construction of marinas, hotels, a shopping center, and several restaurants have turned the islands into a recreational area. It’s also a place where ship lovers can spot all the big ships lining up to transit the Panama Canal.
The island at the end of the causeway, Isla Flamenco, is the most developed. It has a beautiful marina surrounded by several restaurants.
The other islands aren’t as built up but have some attractions of their own. Isla Perico has a small strip of restaurants and shops.
Punta Culebra is the home of the Punta Culebra Nature Center (closed Mondays, admission US$5), while Isla Naos has the Smithsonian Tropical Research Institute and a hotel. Ferries to Isla Taboga leave from the dock at Punta Culebra.
The Frank Gehry-designed Biomuseo, which opened in 2014 (10am to 4pm, closed Tuesdays, admission US$22 for non-residents), is located on the mainland at the beginning of the causeway. I didn’t have a chance to visit.
There is a bike and walking path along the causeway making it a popular place for locals to get some exercise. A taxi from El Cangrejo to the Flamenco Marina cost me US$12. To Casco Viejo it was US$7.