Angostura Bitters (frequently called just 'bitters') is used to flavor ice cream, fruit compotes, etc., but is most commonly known as the essential ingredient in the 'Manhattan' cocktail and Pink Gin.
Ciudad Bolivar is a city in east Venezuela, founded in 1764 as San Tomas de la Nueva Guayana, it was popularly known as Angostura. Here in 1824 a physician, Dr. J.G.B. Siegert first made Angostura Bitters, an aromatic flavoring agent used in drinks and in cooking.
Angostura Bitters is made with a secret blend of various herbs and spices, including cinnamon, quinine, and nutmeg. The original recipe used bark from the Angostura or Cusparia tree (Galipea officinalis). It is now made exclusively in Trinidad.