San Juan hands out its best views for free: a paved trail under the 1539 city wall, plazas open past midnight, and a cemetery on the Atlantic. Add 75¢ AMA buses, US$1.50 Tren Urbano rides and US$2 fritters, and three days barely dent a wallet.
A 0.8-mile paved National Park Service trail hugging the base of the 1539 city wall, running from La Puerta de San Juan out to the headland tip. No ticket booth, no gate fee — just iguanas, cane-pole fishermen and garitas overhead.
A tiny 18th-century chapel capping the bottom of Calle del Cristo, its silver ex-voto altar visible through the grille. The walled park beside it holds hundreds of rock doves nesting in the rampart, with a free terrace over San Juan Bay.
Spain's last military building in the Americas (1864), a three-storey barracks wrapped around a huge public courtyard you can walk into free. Outside, the 40-foot black granite Totem Telúrico marks 500 years above a stepped plaza.
A gas-lamp promenade below the ramparts, from the 1837 jail that now houses the tourism office to the bronze Raíces fountain, where Taíno, African and Spanish figures rise from the spray facing the bay and the cruise piers.
The island's largest public market, trading under a concrete hall since 1955. Stalls stack quenepas, guanábana and recao, juice bars blend batidas for US$3, and back counters ladle arroz con gandules with pernil onto foam plates.
By day a working fruit-and-fish market in a 1910 building; the surrounding alleys hide counter joints selling mofongo, bacalaítos and cold Medalla for a fraction of Condado prices. Daytime is when locals actually shop here.
A former industrial street turned open-air gallery by the Santurce es Ley festival since 2010, with warehouse facades and whole party walls painted by Bik Ismo, Alexis Diaz and visiting muralists. New layers appear each year.
A line of wooden fry shacks along the coast road east of the airport, serving alcapurrias, bacalaítos and pinchos off charcoal drums for US$2-4 each, eaten standing with the Atlantic breaking behind the palms.
Seventy-five acres of bamboo groves, an orchid house, a heliconia collection and a lotus pond, all belonging to the UPR agricultural station. Entry has stayed free for decades and the shaded loops are usually near-empty on weekday mornings.
An 1863 cemetery wedged between the north wall and the Atlantic, its marble angels and the domed neoclassical chapel set against breaking surf. From the rampart above you look straight down into the coloured rooftops of La Perla.
A slim islet at the far side of the bay mouth holding El Cañuelo, the small 17th-century fort that crossfired with El Morro. Picnic shelters, a rocky shore and the single best head-on view of the fortress skyline.
A tidal lagoon between Puerta de Tierra and Condado where manatees surface at dusk and kayakers cross under the 1910 bridge. The seawall walkway and small park cost nothing and catch the sun going down over the water.