In the old town of Kotor there is a very old black poplar (Populus nigra) on a small square. In front of it a sign in two languages (Montenegrin and English) has some information about it:
A centuries-old black poplar (Populus nigra) is the "landmark" of the Piazza of the Cinema in the Old Town. It was planted after the strong earthquake in 1667 in the courtyard of a former Franciscan monastery of Our Lady of the Angels. The poplar, which dates back to the Venetian period, with its intertwined curvy branches and knotted cracked trunk, was and still is the favorite place of tourists and travelers, while for many residents of this part of the city it is the symbol of childhood happiness. Numerous cultural and entertainment programs were and still are being held under the canopy of this majestic tree.
At the time when the Monastery of Our Lady of the Angels was seated here, the poplar was hidden from the public eye and surrounded by a 12 meters high wall. When the wall was torn down, besides the residents of Kotor, excursion groups and numerous tourists came to take a photo of this giant tree in the middle of the square. It is so today. The tree is the symbol of numerous cultural events, especially during the Kotor festival of theater for children.
The sign doesn't say anything about the height or girth of it, but there is an interesting Protection study of the "Agencija za zaštitu prirode i životne sredine" (Agency for Nature and Environmental Protection) about the protection of this particular tree. On page 17 they also state the height and girth.
If it was really planted after the earthquake in 1667 it is one, if not the oldest black poplar worldwide.