It's Saturday night, and disco music is blaring out from a shed-turned-nightclub in Tortuguero.
But as villagers make their way to the hotspot to catch up with friends and have a drink, our group of ten skulk past in waterproof trousers and hiking shoes, armed with insect repellent and torches.
Letting our hair down is not the plan tonight. Instead, we're hoping to see some nesting sea turtles who come to the Costa Rican coast every year.
Our patience pays off, and during a two-hour session, we are rewarded with views of three green turtles.
Our guide, Jonathan Sequeira, tells us that Tortuguero (meaning Land of Turtles) is a favourite place for turtles to lay their eggs, with the endangered green species being the most popular here. Hatching season runs from July to October.
Our first glimpse is a turtle ambling back to the Caribbean Sea, after deciding the hole she has dug on the beach is not suitable for her nest. We then stumble across a turtle slowly walking on the path, so still, I think she isn't real.
But the best is yet to come. Our third and final turtle is laying her eggs - up to 100 in 30 minutes. She then covers the eggs with sand using her back flippers as a shovel, before leaving her babies and returning to the sea.
Nestled between Nicaragua and Panama, Costa Rica is a paradise for animal-lovers, and now it's set to become even more popular thanks to direct flights: Thomson launched a route last November, and British Airways will run a service from May. The whole journey now takes roughly 10 hours.
During my five-day visit, I see sloths (both the two and three-fingered types), iguanas, monkeys (capuchin, spider and howler species), as well as caimans and crocodiles.
On our first day, as we stop off for breakfast on our way to Tortuguero National Park, we spot a sloth cradled in the branches of a tree, with algae growing on its fur.
The humid rainforests and cooler cloud forests in Central America are also home to creatures such as the anteater, Baird's tapir, kinkajou and various lizards. The country boasts 900 bird species including six different toucans, macaws, hummingbirds and the red and green quetzals, considered one of the most beautiful birds in the world.
Wild cats such as jaguars, pumas and cougars also live here, although sightings are very rare, with only 10 jaguars recorded on cameras in the past year.
Staying in the heart of the rainforest at the four-star Evergreen Lodge, in a spacious rustic cabin, I have never felt closer to nature. Barking howler monkeys wake me up in the morning, while the gentle pattering of rain lulls me to sleep at night.
From Tortuguero, we make our way to Monteverde in the north-west part of the country, where the humid and tropical weather is replaced by a cooler climate.
Whizzing through the scenery
Whizzing through the cloud forest on the zip line canopy tour at Selvatura Park is the most fun way to experience Monteverde, although on my first attempt, I'm far too busy freaking out to admire the scenery. There are 13 cables in total - and one measures 1km!
Braver souls can opt for the Superman zip line, where you 'fly' through the forest, with a Tarzan swing at the end of the course.
The cooler weather makes it the perfect spot to grow coffee, as I discover on a trip to the Don Juan coffee plantation.
Our witty tour guide, Junior Ramirez Vindas, who describes himself as a "Don Juan Harry Potter" due to his ability to concoct creative blends, tells us only Arabica coffee is grown in the country.
Even though I've been buzzing on caffeine all afternoon, I find it easy to drift off to sleep at Hotel Ficus, a mountain retreat not far from the Monteverde Cloud Forest Reserve. The rooms offer a breathtaking view of the surrounding area.
I lie in bed dreaming about coffee, chocolate and capuchin monkeys. It's no wonder Costa Rica is one of the happiest countries in the world. (According to the UN-affiliated 2015 World Happiness Report, it ranks 12th place.)
"We don't think we are the happiest people in the world," Jonathan says. "But life is good for us, and we are lucky here."
I couldn't agree more.
Shereen Low was guest of Hayes & Jarvis (01293 735 831) who offers a seven-night 'Highlights of Costa Rica' holiday from £1,499 per person - saving up to £277 per person. The offer includes one night at the Hotel Balmoral in San Jose, two nights at the four-star Evergreen Lodge Hotel in Tortuguero, one night at Los Lagos hotel in Arenal, followed by a further night at Hotel Ficus in Monteverde and finally two nights at Casitas Eclipse Hotel in the Manuel Antonio National Park. Includes direct return international flights from London Gatwick to San Jose with British Airways.
Photo credit: PA Images/Jonathan Sequeira, PA Images/Ernesto Brandon