Guanacaste is Costa Rica's driest province and the one that most resembles a conventional beach holiday: reliable sun, tropical dry forest instead of rainforest, and a succession of bays down the Nicoya peninsula.
Where, and for whom
Tamarindo is the most developed and the easiest: surf schools on every corner, forgiving waves for learners, nightlife and plenty of services. It is also the most touristy, which suits some people and repels others.
Nosara, specifically Playa Guiones, combines a consistent clean break with a community heavily oriented towards yoga and wellness; local rules have limited building near the beach, so it stays far greener. Santa Teresa and Mal País, at the southern tip of the peninsula, are more remote, with dirt roads, a young crowd and more powerful waves.
For anyone not surfing: Sámara has a reef-protected bay with calm water ideal for families, and Playa Conchal is made of millions of shell fragments rather than sand, giving a turquoise unusual for the Pacific.
Wave seasons
There is surf year-round. The bigger southern swells arrive between April and October; from December to April offshore winds groom the surface in the mornings. For learning, any time works; for serious waves, mid-year.
Turtles
Playa Ostional hosts arribadas: mass arrivals in which tens of thousands of olive ridley turtles nest over a few nights, usually between July and December and around the last quarter moon. It is a regulated phenomenon, accessible only with an authorised local guide. At Playa Grande near Tamarindo, leatherbacks nest from October to March.
Beyond the coast
Inland, Rincón de la Vieja National Park offers a completely different landscape: fumaroles, bubbling mud pots, waterfalls and dry-forest trails. It makes a good day trip from the coast.
Practical
Liberia international airport is far closer than San José and saves five hours of driving. Many secondary roads on the peninsula are dirt with river crossings; in the wet season you want a vehicle with real clearance and four-wheel drive. And be aware that March and April in Guanacaste are genuinely hot.
The dry forest
Guanacaste protects one of the last significant stretches of Central American tropical dry forest, a habitat far rarer than rainforest because it grows on land that is easy to clear for cattle. In the dry months the trees drop their leaves entirely and the landscape looks dead; within days of the first rains in May it turns green and flowers. Santa Rosa and Guanacaste national parks are the places to see it.