Science writer and explorer Gaia Vince goes to Costa Rica to find out how this remarkable little republic has become, ‘the happiest, most sustainable country in the world!’

Costa Rica runs its national grid on rivers and volcanos and by 2021 it will be carbon neutral. It has no military and its rainforest is actually increasing.  It is home to more than 500,000 species.

In episode 1 Gaia helps capture a rogue crocodile before travelling to the incredible Monteverde Cloud Forest and scaling a giant tree with scientists who preserve the delicate forest life forms.

From there she goes to meet the charismatic president of Costa Rica, Luis Guillermo Solis, who explains why Costa Rica puts environmental protection at the top of the national agenda.

On the Caribbean coast of the country, Gaia gets up close and personal with the most iconic animal in Costa Rica – the sloth.

She then travels with the family to celebrate Kip’s 4th birthday on the remote and wild Osa Peninsula.

In episode 2 Gaia goes whitewater rafting down Costa Rica’s most spectacular river to a remote ecolodge, to meet the people who fought to save the river from being dammed – then visits the largest hydrodam in central America.

She treks into the exclusion zone of an active volcano, and takes a dip in a hot spring, to understand how Costa Ricans have harnessed one of nature’s most destructive forces.

And on the stunning Pacific coast, she helps build artificial reefs made from the most unlikely recycling materials.

In the final episode Gaia goes horse riding with a 99 year old cowboy, takes a canoe trip to meet the indigenous Bri Bri and witnesses an incredible natural phenomena as thousands of Olive Ridley turtles arrive onto a remote Costa Rican beach to lay their eggs – known as an ‘arribada’.