Guanacaste

Tropical dry forest once ran in a broad band down the Pacific side of Central America and very little of it survives; the stands protected in this province are among the most significant remaining anywhere. What makes it worth planning around is that it is two entirely different places depending on when you come. In the dry months the trees stand bare, the light is hard and golden, dust hangs over the ranch roads, and the wildlife concentrates around whatever water is left — which makes this the easiest place in Costa Rica to see animals without a guide finding them for you. Howler monkeys, white-faced capuchins, coatis, iguanas the size of cats, and an extraordinary density of birds gather in the riverine strips. In the green months the same forest is dense, humid and loud, the dust roads become mud, and the wildlife disperses because water is everywhere. Neither is the better version; they are different destinations sharing a map. What catches people out is expecting the postcard rainforest and finding, in February, something closer to a savannah. Knowing that in advance turns a disappointment into the most interesting thing about the province.

The province's interior rises into a volcanic range, and the protected areas along it are the reason to leave the beach for a day or two. The best known offers a genuinely unusual walk: a marked trail past bubbling mud pots, steam vents and a small hissing crater in open forest, with a separate set of trails dropping to waterfalls and swimming holes in the ravines below, and naturally heated rivers and pools at the base of the mountain where the geothermal water surfaces. It is a rare combination of volcanic landscape and easy access, and it can be done as a long day from most of the northern beaches. Elsewhere in the range the dry forest is protected in large blocks that see very few visitors and reward anyone willing to walk in the heat. Down on the flats, the wetlands along the province's major river are an important waterbird site: in the dry season, when water elsewhere has gone, the concentrations of herons, storks, spoonbills and waterfowl are exceptional, and a slow boat along the river is one of the better wildlife half-days in the country. Bring far more water than feels necessary for any of it — the health and safety guide treats heat and sun as the real risks here, and they are.

Guanacaste's shoreline is deeply indented, and the practical consequence is that its beach towns do not form a continuous resort strip — each sits at the end of its own road off the inland highway, so moving between two neighbouring beaches often means driving inland and back out again. That geography is why the towns have kept genuinely distinct characters. Some are surf towns with a young, transient, board-carrying population and a main street of rental shops and casual food. Some are quiet retirement and yoga communities with dirt roads, a strict low-rise feel and almost no nightlife. Some are working fishing villages where tourism is a sideline. And a stretch of the north holds the country's largest resort developments on a peninsula of manicured bays. The surf is the coast's headline draw and it is genuinely world-class, with a spread of breaks that suits beginners in some bays and only experts in others — worth asking locally rather than guessing, because the difference between them is not visible from the sand. Two beaches on this coast are major sea-turtle nesting sites, one for leatherbacks in the early part of the year and one famous for mass arrivals of olive ridleys, which come ashore in enormous synchronised waves several times a year. Both are managed with licensed night visits and strict rules, and both are worth building a trip around if the timing falls right.

The interior of the Nicoya peninsula, in this province's south-west, is one of a small handful of regions worldwide identified as places where people live unusually long lives — a designation that has brought a certain amount of wellness tourism with it and which, on the ground, looks like nothing at all: inland villages, maize and beans, water from particular aquifers, people still working outdoors in their eighties, and a pace that has not been organised for visitors. It is worth knowing about precisely because there is no attraction to visit. What there is, if you drive the interior rather than the coast road, is very good simple food and a part of Costa Rica that tourism has barely touched. Inland Guanacaste more broadly is cattle country and has been for a long time, which gives the province a culture the rest of Costa Rica does not share: horsemanship as an ordinary skill, its own marimba music and dances, an ox-cart craft tradition, and a plainer, older style of cooking built on corn, rice, beans and cheese rather than on the coastal Pacific's seafood. Several working ranches take visitors for riding and for the ordinary daily work of the place, which is a better use of an inland day than it sounds. The other side of a six-month dry season is that water is a real and growing constraint here — supply restrictions in the driest months are a normal part of life in some towns, and using water thoughtfully is a straightforward courtesy rather than an abstraction. As for getting here, the province has its own international airport near the provincial capital, which puts the northern beaches within an hour of arrivals rather than the five they would be from the capital; the transport guide explains why flying into one Costa Rican airport and out of the other is the single most useful thing most itineraries never do. A car is close to essential once you are here, given that bay-to-bay geography, and the trip-planning guide makes the case for pairing this coast with the volcano country inland rather than trying to add a third region.