pepenno

Updated: July 17, 2026

The innermost vault of this astonishing structure forms a semicircle eighteen Roman palms wide, and as many high: this is inclosed in a second vault, and that again in a third, all formed of hewn blocks of pepenno, fixed together without cement. So extensive were these channels, that in the reign of Augustus the city was subterraneously navigable.

Oliver Goldsmith - Pinnock's improved edition of Dr. Goldsmith's History of Rome : to which is prefixed an introduction to the study of Roman history, and a great variety of valuable information added throughout the work, on the manners, institutions, and antiquities of the Romans; with numerous biographical and historical notes; and questions for examination at the end of each section. : By Wm. C. Taylor.