Apple CEO Tim Cook visits Slovenia

Cook took part in a cave tour called In the Footsteps of Luka Čeč, which takes the visitors along the trails of the first cave explorers.

As part of the tour, he also visited Pivka Cave and Black Cave, the Postojna Cave operator said on Saturday. Cook was interested in learning more about the cave's most famous inhabitant, the olm or "human fish" as it is known in Slovenian, as well as about the history of the cave, reads a press release.

Cook was also received by the operator's directors Kaja and Lana Batagelj.

In the Postojna Cave visitors book he wrote that everyone in the world should see the marvels of the cave, which are hard to put into words, as he thanked the organisers for the amazing tour.

One of the biggest tourist attractions in the country, the Postojna Cave has long been a place attracting high-profile visitors, from emperors of the Austro-Hungarian Empire to modern-day heads of state and other famous personalities.

A few days ago Cook was also spotted in Ljubljana, which elicited speculations about the nature of his visit to Slovenia.

It is believed to be an informal visit. Before making a stop in Ljubljana, he visited the Venice Film Festival. According to the city's news portal Ljubljanainfo, neither the Ljubljana municipality nor the Ministry of the Economy, Tourism and Sport were informed about his visit.

Cook joined Apple in 1998 as a senior vice president for worldwide operations, and then as executive vice president for worldwide sales and operations.

He took over as CEO in 2011, after Steve Jobs, who died from cancer later that year, resigned.