The Memorial Tomb of Alexander I of Battenberg, better known as the Battenberg Mausoleum in Sofia, the capital of Bulgaria, is the mausoleum and final resting place of Prince Alexander I of Bulgaria, the first Head of State of modern Bulgaria.
Commissioned to the Swiss architect Hermann Mayer, designed in the eclectic style and opened in 1897, the mausoleum measures 11 metres in height and 80 square metres in area. The interior was painted by the noted Bulgarian artist Haralampi Tachev. The Battenberg Mausoleum is located at 81 Vasil Levski Boulevard. It was partially restored in 2005.
Wikipedia https://en.wikipedia.org/wiki/Battenberg_Mausoleum
Address 4 улица Ф. М. Достоевски, София 1000, Bulgaria
Coordinates 42°41'29.464" N 23°19'56.855" E