Our next stop was Old San Juan, intended to serve as a base for the rest of the trip. Since we've been told public transit is extremely difficult to navigate in Puerto Rico, we opted to rent a car ($300 with insurance).
We had lunch at Cafe Manolin, which seems to be some of the most authentic Puerto Rican food thus far. Dishes consist mostly of your choice of meat, plus beans and rice. Try the house-made hot sauce, which resembles mustard and is pleasingly spicy. Prices, while still not cheap, were lower than in Vieques, and the food was noticeably better.
Old San Juan is an attractive colonial neighborhood with pastel-colored buildings and cobblestone streets, well-situated for aimless wandering. Most stores and restaurants close early, around 6pm, which is unusual for Latin culture.
The next day, we loaded up the rental car and drive the hour to El Yunque, Puerto Rico's kid-tested mother-approved rainforest. La Mina and Big Tree trails were an easy walk along a paved footpath through the forest, but overrun by umbrella-wielding tourists. The two trails converge at the falls, where you can dip into the water, but we were deterred by the crowds. Up the trail a bit, the slightly intrepid can walk off the trail into a more private pool to take a dip.
Mt. Britton trail, further up the mountain, was more rewarding. It's a steep 40 minute hike up to a tower; climb the rain-streaked steps for beautiful views of the island.
Returning to San Juan, we had dinner at El Jibarito, which is another authentic eatery with a menu replete with mofongo, rice and beans, and tostones. The chicken stew with garlic mofongo was delicious, as was the coconut flan. Steer clear of the tamale.