Discover the Skocjan Caves in Slovenia

As we entered the caves, the temperature dropped immediately and the path became narrow, with low ceilings. This was the man-made tunnel into the vast, underground caverns.

Eventually, we emerged from the passage into the natural cave and found ourselves in a series of caverns, connected by a walkway. Spotlights highlighted the trail and key features of the cave around us, including some impressive stalactites and stalagmites adorning the ceiling and ground - the largest stalagmite in Škocjan Caves is over 47m from the ground to its tip.

Following the guide closely (no one wanted to be left in darkness when she turned out the lights), we came into an enormous empty space, with the gushing of water clearly audible and the river below barely visible.

We were looking at the great underground gorge of the Škocjan Caves, a truly remarkable and awe-inspiring space to see. Everything - bridges, boulders and stalagmites - looked small in this huge space.

Crossing the underground canyon is the Cerkvenikov Most, a slender bridge spanning the gap high above the river. Walking across it was an unforgettable and slightly terrifying experience, and I was reminded of a scene from the Lord of the Rings.

Soon after we crossed the bridge, we could see daylight in the distance, and we emerged from the cave into the sunlight, with beautiful greenery and the rushing Reka River at our feet. The subsequent walk along the river was gorgeous and light, but couldn't compare to the majesty of the dark caverns below.

Visitors have three choices on how to experience the caves:

• a guided tour through the underground canyon

• following the Reka River underground

• walking along the surface, following the Škocjan Education Trail.

The most popular way to visit the caves is by taking a guided tour through the caves (16-24 euros per adult, depending on the time of year). It's a 3km route, with some remarkable sights along the way. You can also do an organised day trip to the caves from Ljubljana, which includes this route.

Another option is to follow the Reka River on its path underground. This 3.5km route starts at the cave's natural entrance near the Škocjan village and allows you to choose whether or not to walk independently or with a guide.

If you'd rather not venture underground, the Škocjan Education Trail is a 2km circuit around the Big and Little Collapse Dolines, natural compressions in the earth, home to some interesting wildlife. It also takes you through the villages of Betajna, Matavun and Škocjan and, once again, you can go with a guide or by yourself.

Regular guided tours through the underground caverns are available from April through to October. The aboveground walkways are usually accessible all year round. Check the official website to confirm tours are available when you visit.

The Škocjan Caves are located 4km from the town of Divača in southwestern Slovenia. From Ljubljana, it takes around an hour to drive to the caves and there is also public transport available.

There's a regular train from Ljubljana to Divača and it's an easy walk from the station to the caves, with a footpath and good signage. During the summer months, there is also a shuttle bus from the train station to the caves.

You can also do an organised tour to the caves from Ljubljana if you prefer.

Over more than a million years, the immense Škocjan Caves have been moulded by the Reka River flowing beneath the ground. The river's source is 55km away, where the river flows above ground, before entering the caves through a passage and flowing underground for over 35km.

These caves are wonderful examples of karst, where water has carved out the impressive the caves over a long period of time. The travertine terraces which water created as it flowed down the limestone are still visible in the caves.

Eventually the river enters the Škocjan grotto through a passage and travels for more than 35 kilometres (20 miles) underground. The Škocjan Caves are great examples of karst, where dissolvable rocks (like limestone) are shaped by running water.

According to archaeological studies, people have lived in the caves and surrounding areas for more than 10,000 years, including the Mesolithic, Neolithic, Bronze and Iron Ages right up to the Middle Ages

If you're spending some time in Slovenia, head to the beautiful capital of Ljubljana next, and if you're interested in seeing more caves, visit Postojna Cave in south-western Slovenia.

Otherwise, consider making your way towards the coast and the lovely town of Piran. From there, it's an easy trip to Croatia and the stunning Dalmatian Islands.