Toynbee "Colonne d'Ercule"
the Pillars or Columns of Hercules, i.e. Mt. Abyla (Jebel Musa) in N. Africa and Mt. Calpe (Gibraltar) in Spain, so called from the tradition that they were originally one mountain, which was torn asunder by Hercules; they were supposed to mark the W. limit of the habitable world. Brunetto Latini says:

. . . en Espaigne . . . est la fins de la terre, selonc ce que les ancienes gens proverent; et meismement le tesmoignent li tertre de Calpe et de Albinna (ou Ercules ficha ses colombes quant il venki toute la terre) ou leu ou la nostre mer ist de la mer ocheaine, et s'en vient parmi ces. ii. mons (ou sont les illes Gades et les colombes Ercules. ({Latini. Trésor. i. 123}.)

And in the Tesoretto:

Appresso questo mare
Vidi diritto stare
Gran colonne, le quali
Vi mise per segnali
Ercules il potente,
Per mostrare alla gente,
Che loco sia finata
La terra, e terminata.
({Latini. Teseretto. xi. 119-26}.)

Ulysses (in Bolgia 8 of Circle VIII of Hell) refers to the Pillars of Hercules in connexion with the Strait of Gibraltar, which he describes as quella foce stretta / dove Ercule segnò li suoi riguardi, [Inf. xxvi. 107-108]; they are spoken of as the W. limit of the habitable world, 'termini occidentales ab Hercule positi', Quest. 54. [Calpe: Gade: Setta.]

©Oxford University Press 1968. From A Dictionary of Proper Names and Notable Matters in the Works of Dante by Paget Toynbee (1968) by permission of Oxford University Press