The CARSO is the Italian name for the strip of limestone uplands that rise from the Venetian plain south of Monfalcone and eventually merge into the Istrian plateau. The particular shape and look of the karst landscape is due to the weathering of the limestone bedrock by water and wind. Although within a thirty-minute bus ride of Trieste, it feels like an entirely different country, and is geologically, botanically and demographically distinct from anywhere else in Italy. Most of the Carso now lies within Slovenia (its Slovene name is Kras), and even the narrow strip inside Italy, though supporting a population of just 20,000, remains distinctively Slovene in culture, boasting places with names like Zagradec and Koludrovica. The thick-walled houses seem built to withstand the blasts of the bora, the fierce northeasterly wind which can reach gusts of 90mph. When it’s at its worst ropes are strung along the steeper streets in Trieste and old folk stay indoors.
Like all limestone landscapes the environment is harsh: arid in summer and sometimes snowbound in winter. The surface of the plateau is studded with sink-holes left by streams which have formed vast caverns, underground lakes and rivers.
The distinctive landscape and unspoiled natural environment make for fine walking. If the scenery isn’t as grand as the Dolomites, the pace is gentler, and you can stop for refreshments at an osmiza.Read More
The Grotta Gigante is the Carso’s main tourist attraction, and with good reason: it’s the world’s largest accessible cave, and the second-largest natural chamber anywhere in the world. As it’s 98m high by 76m wide, the dome of St Peter’s would fit comfortably inside. It’s a steady 11°C inside, so bring warm clothes.
The cave is impressive in scale and, like most of the caves in the Carso, was created by the erosive action of a river, in this case the Timavo, which sank deeper and deeper underground before changing course (the cave is now dry). The fantastically shaped stalactites and stalagmites were formed by deposits of calcium carbonate and colourful metal oxides. Much more recently, ferns and moss have started to grow in what was previously a lifeless environment, thanks to photosynthesis triggered by electric lighting. The two long “pillars” in the centre of the cave are in fact wires sheathed in plastic. At the bottom end two super-accurate pendulums are suspended, used to measure seismic shifts in isolation from surface noise and air currents.
Walking in the Carso
Walking in the Carso
The tourist office publishes a useful map of the network of numbered footpaths in the Carso; it shouldn’t be used for serious navigation but is a useful guide. For serious hiking in the hills you need Tabacco’s Carso Triestino e Isontino Map #047. Two walks near Trieste can be particularly recommended:
The Strada Vicentina
Also known as the Napoleonica, the Strada Vicentina is some 3.7km long, contouring the hillside above the city, between the Obelisco campsite and the hamlet of Borgo Nazario (near Prosecco). It’s a scenic, easy walk, partly shaded by trees and partly cut through almost sheer limestone cliffs; on a clear day the views are superb. Access to the Strada Vicentina couldn’t be simpler: Obelisco is a stop on the tranvia, and the Borgo Nazario end is near Via San Nazario, where the #42 bus stops on its way back to Trieste station.
The Val Rosandra
A miniature wilderness of limestone cliffs and sumac trees, the Val Rosandra is the local rock-climbing headquarters and is crisscrossed with walking paths. From the bus stop at Bagnoli Della Rosandra (bus #40 from Trieste), follow the road behind the square to Bagnoli Superiore where the marked hiking trails begin. Highlights include the remains of a Roman aqueduct, the little sanctuary church of Santa Maria in Siaris, and various pools and waterfalls. If you get as far as the tiny hamlet of Bottazzo – the last habitation before Slovenia – you’ll see a sign indicating a friendship path linking communities on either side of the frontier.
Perhaps the best way to experience the Slovene culture of the Carso is to find an osmiza, a rustic eating place where farmers sell their own produce, such as cured meats, cheese, olives, hard-boiled eggs, bread and wine. The name comes from the Slovene word osem, “eight days”, which was the period of time allowed by imperial edict for the peasants to sell their wares. The food is simple and cheap, and the locations often stunning. The problem with osmize is that they have limited opening times, vary hugely in quality, and are hard to find – which makes tracking down a good one all the more difficult. Ask the tourist office for a list or look at winterware.it/tsr/ambiente/carso/osmizze.htm (Italian only). Otherwise, as long as you don’t mind taking a few detours, just take a #44 bus from outside the station in Trieste, get off at the villages Prosecco or Contovello, and start asking if there is an osmiza nearby. You’ll know you’re getting close when you see wooden signs and branches of ivy suspended from archways and lampposts.