In a country with thousands of caves, Škocjan is the one we take our own visiting friends to. You walk through an underground canyon carved by the Reka River, across a footbridge set almost 50 metres above the water, through halls large enough to hold a cathedral. It is UNESCO-listed, and far quieter than Slovenia's busier show caves, which is exactly why we chose it for this route.

On the way to the coast you stop at Socerb Castle, perched on the edge of the Karst plateau with the whole Gulf of Trieste below. Then Piran, five centuries of Venice in one compact old town: narrow lanes, Tartini Square, the little harbour, time for a seafood lunch by the water, and in the summer months enough free time for a swim in the Adriatic. Your guide knows which konoba is worth your hour.

We keep the group to 8 in a comfortable van so the day stays flexible: your guide suggests optional stops beyond the set itinerary, admissions stay optional with prices shared upfront, and the same local team has run this route since 2011, today as official Gray Line Slovenia licensee.

Who is this tour for?

• First-time visitors: Slovenia’s most dramatic cave and its prettiest coastal town in one day, no car needed
• Nature lovers: the underground canyon of the Reka River, a UNESCO World Heritage site since 1986
• History buffs: five centuries of Venetian Piran, and Socerb Castle above the Gulf of Trieste
• Couples, families and solo travellers: an easy-paced small-group day with a seafood lunch and, in summer, a swim in the Adriatic