Our first stop of the day in Slovenia was Postajna Cave. Apparently, it is the most visited tourist cave in Europe! To enter the chambers, you need to take a short ride in (3.7km) on the cave railway, which has been in existence for 140 years.
From there, it was about 1.5 hours of walking (5km) while observing the stalactites and stalagmites. Throughout the entire duration, you will be accompanied by a guide who would call out numbers at certain points for you to press on the audio guide.
Our last destination in Croatia was Zagreb, the capital of Croatia. The city is quite chilly as it is 122m above sea level. It is relatively easy to get around the city as they have an excellent network of trams, buses and trains.
The statue of Saint George and the Dragon located in front of the Stone Gate.
I could not get a good shot of the miracle painting of Virgin Mary at Stone Gate because I felt weird taking a picture while people were doing their prayers. This picture is taken from the website of Absolute Croatia.
Here is a background of the painting: A great fire broke out in 1731 and burned down 50 buildings, including the chapel that the painting was in. However, after the fire, the painting was found undamaged! And since then, the painting has been a symbol of hope and was displayed at Stone Gate.
We visited the Old Town of Mostar and the famous Mostar Old Bridge on the river of Neretva in Bosnia and Herzegovina. The name Mostar was derived from medieval bridge keepers, mostari, who protected the bridge since the 16th century.
(Source: https://www.reddit.com/r/travel/comments/4yox3u/taken_yesterday_stari_most_old_bridge_in_mostar/)
The country went through a war in 1993 and the bridge, which had stood strong for 427 years, was destroyed during that period. It took many years to rebuild the bridge, and it was finally reconstructed in 2004.
From Dubrovnik, we took a day tour to Kotor, which is a coastal town in Montenegro and the only town on the eastern coast of the Adriatic Sea. It is also one of the best preserved medieval old towns in the Adriatic and hence, recognised by UNESCO as a World Heritage Site.
The first thing you notice about the town is the fortifications, which are about 4.5km long and have been around for centuries.
The Saint Tryphon Cathedral, which was built in 1166, but was damaged during two massive earthquakes, one in 1667 and another in 1979. It had to be rebuilt after both disasters.
We travelled from Zadar to Split and finally to the town of Ston, which is located at the Southern tip of Croatia. The journey from Split to Ston took half of the day.
To get to Ston, we had to go through immigration at Bosnia and back into Croatia again. The checkpoint was quite efficient.
As we got closer to Ston, we noticed a great wall. The inner Walls of Ston surrounding the town is about 890m in length and the one outside town was about 5km. The 14th-century wall was initially about 7km long, but there was some demolition work done by the government, and the stones were taken to build other facilities.
We had fish for lunch (again).
Our next stop was Zadar, the oldest continuously inhabited city in Croatia.
One of a kind Sea Organ, an architectural feat! It is hard to capture from this angle as this is the back of the organ, but what happens here is that music is created by the sea waves entering the tubes located underneath. You can see many people sitting along the organ, just admiring the view and the harmonic sounds.
The Church of Saint Donatus, which is circular in shape and 27m high.
The Landward Gate, with the Lion of Saint Mark, a symbol of the Republic of Venice. Zadar was conquered by Venice from 1202 to 1358 and 1409 to 1797, and the legacy is still evident.
I must state that December was definitely not the best month to visit the scenic national park of Plitvice Lakes. The trees were barren, and the colours turned out quite cold in pictures. As I was researching about the location, the best period seems to be Autumn when the leaves turn to various shades of yellow, orange and red.
The national park is the oldest in Southeast Europe and the largest in Croatia. It boasts 16 lakes with 92 cascades and waterfalls, making it a World Heritage Site in 1979. 
