Cafetería Rolando bombing
1974 CE.
Shown on the map at 40.416°, -3.704°.
The Cafetería Rolando bombing was an attack on 13 September 1974 at the Rolando cafe in Calle del Correo, Madrid, Spain which killed 13 people and wounded 71. Though no claim of responsibility was made, the attack is widely believed to have been carried out by the armed Basque separatist group ETA.
Text from the Wikipedia article Cafetería Rolando bombing, licensed CC BY-SA 4.0.