This hiking adventure leads through La Mancha in Spain. You’ll explore an area where a vast plain melts into a limestone plateau and Don Quixote's windmills transform into gigantic rock formations.

The Calares del Mundo, Calar de la Sima Natural Park, and the Calar de la Osera are unique areas in La Mancha. Here, the mountains are high, and beautiful waterfalls plunge in crystal-clear pools; deer, wild boar and golden eagles live in the dense forests; and lunar landscapes decorate the summits of the Calares.

The GR 66 is one of the long-distance footpaths that crosses Castilla La Mancha from north to south in 600 kilometres (370 mi). Although the route is not yet entirely signposted, an ambitious project is underway to connect it with the GR 7, GR 10 and GR 24.

In this Collection, I present a circular route that runs through the three calares in the southwest of Albacete on the border with Andalusia. Here, the GR 66 is split into three variants: the Calar de la Sima Trail (GR 66.1), the Calar del Mundo Trail (GR 66.2) and the Calar de la Osera Trail (GR 66.3). Spending six days in the mountains of Albacete is an unbelievable adventure that's impossible to forget.

Each day takes you into the interior of the Sierra to discover a different part of the Calar. You'll immerse yourself in nature, far away from any civilisation. You're unlikely to have phone reception and you won't find any opportunities to resupply, so I’d recommend checking you have enough food and water in your rucksack before you start walking each day.

All stages end in mountain villages where you can find accommodation and supplies in local shops or restaurants. Don't forget to book your accommodation in advance to avoid last-minute surprises.

Except for the last day, all the stages are quite long and demanding so you'll need to be in good shape to enjoy the experience to the fullest. Also, trekking poles can be very useful on the steeper sections.

The best time to explore these mountains is definitely spring when the Mundo River and the streams reach their maximum flow. Temperatures are milder and the landscape is dressed in vibrant, cheerful colours. Autumn offers similar temperatures and warmer hues, but the days are shorter. Winter is colder and you may find snow at higher altitudes. Summer, on the other hand, is hot, reaching over 40 degrees Celsius in the middle of the day. Whatever your choice, be sure to check the weather forecast before leaving home.

Public transport to get to Riópar is very limited. It is possible to get there by bus and combine it with the taxi service. You can check the timetables here (in Spanish): riopar.es/pueblo/horario-de-autobuses. Travelling by car is the most comfortable option and it's easy to find free parking.

Now it's time to pack your rucksack and get going – enjoy the Calares hike!