Alexander Nevsky Cathedral

The St. Alexander Nevsky Cathedral is one of the largest Eastern Orthodox cathedrals in the world. Its beautiful interior is decorated with Italian marble Brazilian onyx alabaster and other luxurious materials. The decor is one of the churches many features that attracts tourists making it Sofia’s primary tourist attraction.

The 12 bells that ring in the clock tower of the church weigh almost 23 tons in total. One of the bells weighs 12 tons along with a tongue of 780 kg and the smallest bell weighs only 10kg.


Georgi Nadjakov a Bulgarian physicist experimented investigating the photo conducting properties of sulphur which led to his discovery of the photoelectret state. Its practical application led to the invention of the modern day photocopier by Chester Carlosn some years later.