( CNN ) -- Just ten miles south of the Polish city of Krakow is a remarkable place carved from salt . Hidden 1,000 feet ( 305 meters ) underground lies a dimly-lit labyrinth of subterranean chambers , with saline lakes , horses ' stables , a chapel and even a salt-sculpted hall . Decorated with elaborate sculptures -- the most astounding perhaps being `` The Last Supper '' carved into a rock salt wall -- even the crystals of the chapel 's chandeliers are hewn from salt , dissolved and reconstituted to resemble glass . It might sound like something out of a Jules Verne novel , but the Wieliczka salt mine is not science fiction but one of Poland 's 13 UNESCO Cultural World Heritage sites , many of which date back to the medieval period . Warsaw 's Old Town ( meticulously reconstructed after 85 % of the capital 's historic center was destroyed during the war ) and Auschwitz Birkenau concentration camp are must-visit spots . But beyond them , you can find hundreds of years ' worth of fairytale-like medieval history . Deeper underground . Few places capture the imagination like the salt mine at Wieliczka , believed to have been completed in 1280 . Tourists can delve into its depths on guided tours . `` You see a little more than 1 % of the mine on the tourist route , '' said Marek Strojny , a guide for more than 20 years . Consider that the tourist route is three kilometers ( 1.8 miles ) long and takes three hours to explore . `` It would take years to see all of the mine , '' said Strojny . `` There are nine levels , with 300 kilometers ( 186 miles ) of tunnels and more than 3,000 chambers . '' Tourists view the mine at just over 300 feet ( 91 meters ) below the surface , but its intricacies continue down for more than double that depth . Mining here was dangerous work ; there were cave-ins , and occasional methane explosions . This accounts for why the miners built the chapel in the 14th century -- they prayed constantly for their safety , and carved religious figures in their spare time . ( Strojny estimated `` The Last Supper '' alone would have taken a year to complete . ) However , the job came with its perks . `` There was great respect for the miners among the community on the surface , '' he noted . `` And they were given privileges by Polish kings . For example , each worker was allowed to carry three kilograms of salt to the surface with them each month and sell it . Salt was ( a valuable ) preservative and was almost as expensive as silver . '' `` Vampires '' in Krakow . The salt would doubtless have been traded at Krakow 's Rynek Glowny , the largest medieval market square in Europe and the site of another intriguing underground voyage . In 2005 , an archaeological dig in the square was intended to last six months , but stretched into five years , such was the volume of treasures exhumed . The result is Rynek Underground , a subterranean museum built under the square . `` The square has risen about four meters since early medieval times , '' said Dominik Lulewicz , an archaeologist at the museum . `` Over the years , the debris from earlier phases ( of the square 's history ) was spread across its surface . '' READ MORE : Krakow becomes world center for literature . While the entire historical center of Krakow is a UNESCO site , the 40,000 square meters of Rynek Glowny is its beating heart . In the 14th and 15th centuries it was a major center of European trade , abuzz with merchants selling everything from luxury goods ( such as silks and spices ) to cloth and lead . As well as seeing some of those treasures , visitors to the museum can also see reconstructions of burial sites that were discovered during the dig , including what Lulewicz called `` anti-vampiric burials '' . `` There are a few with tied hands and legs , probably due to the remains of Pagan beliefs , '' he said . Choosing their religion . Diversity of belief is a uniting facet of Poland 's UNESCO heritage sites . Among the prettiest listed monuments are the wooden churches of Malopolska . Winding through the looming mountains and sprawling fields of this picturesque pocket of south east Poland , are 1,500 kilometers ( 932 miles ) of trails that take hikers past striking examples of timber churches in everything from Roman Catholic to Greek Orthodox styles . READ MORE : Bison thrive in Poland 's wild woods . `` The multicultural history of Poland is marked by the variety of houses of worship from different periods , '' said MaÅ‚gorzata Trelka , of the National Heritage Board of Poland . She pointed to the 18th and 19th century wooden mosques that can be found in north east Poland by way of example . Indeed , Trelka revealed that a 14th UNESCO site has been approved -- wooden Eastern Orthodox and Greek Catholic churches , dating from the 16th to the 19th centuries , in the Carpathian mountain range . And yet another enduring example of Poland 's long tradition of religious tolerance is the UNESCO-listed Churches of Peace in Jawor and Swidnica . These 17th century Protestant churches were permitted by a Catholic emperor following the Thirty Years war , which had sprung from those very religions ' rivalry . But maybe what unites these sites most of all is that , whether deep underground or spread throughout the countryside , Poland is rich in a tangible cultural landscape .
Poland has 13 cultural UNESCO world heritage sites . The Polish government is planning to build a new museum in the city of Krakow, which will be dedicated to the victims and survivors of World War II. The whole of the historic center of Krakow is declared a heritage site .