Star trails form over the Memorial House of the Bulgarian Communist Party on mount Buzludzha in this long exposure picture taken on September 12, 2014. The monument was officially opened in 1981 by the Bulgarian Communist regime to mark 100 years of the set up of an organised Socialist movement, a predecessor of the Bulgarian Communist Party. The monument, no longer maintained by the Bulgarian government after the fall of the Communist regime in 1989, is now abandoned and vandalized. (Photo by Stoyan Nenov/Reuters)

An aerial view shows a sinkhole 3.5 km (2 miles) to the east of Solikamsk-2 mine in Perm region, November 20, 2014. Shares in Russia's Uralkali, the world's top potash producer, fell sharply for a second day on Wednesday after a mine accident that could reduce global supplies and push up prices of the crop nutrient worldwide. Uralkali shares have fallen 28 percent since Tuesday when it suspended work at its Solikamsk-2 mine, which accounts for a fifth of the company's output and 3.5 percent of global capacity, following an inflow of water. A sinkhole, stretching 30 by 40 metres (yards), found at an abandoned mine 3.5 km (2 miles) to the east, increased concern about the future of the mine because an inflow of water and the resulting sinkhole in 2006 forced another Uralkali operation to shut permanently. (Photo by Reuters/Press service of Uralkali company)

Emilia Pechinkova, a 24-years-old Bulgarian Pomak (Bulgarian speaking Muslims) bride poses for a photograph following the “gelina” or face painting ceremony carried out by female guests and relatives in preparation for her three-day wedding ceremony in the village of Draginovo, 100 kms southeast of Sofia on April 22, 2016. Bulgaria's Muslim population is one of the highest in the European Union. During the Communist regime religious rituals were not tolerated, and Muslims were forced to abandon wearing their traditional wedding outfits. Recently, more young Pomak women want to include traditional wedding customs that were forbidden during the regime, regardless of their secular lifestyles and the high cost of such a wedding. (Photo by Nikolay Doychinov/AFP Photo)