Neve Shalom Synagogue massacre
1986 CE.
Shown on the map at 41.027°, 28.972°.
The Neve Shalom Synagogue massacre happened on 6 September 1986 when a group of suspected Abu Nidal Organization terrorists killed 22 worshipers inside the Neve Shalom Synagogue in Istanbul, Turkey.
Text from the Wikipedia article Neve Shalom Synagogue massacre, licensed CC BY-SA 4.0.