On the western side of the Lateran fortress is another great foss, between the Cœliolum and the east end of the Cœlian Hill. It was either thought more convenient to make a bank across that great foss for the aqueduct to rest upon, or this bank which traverses that great foss had been made before for an upper road, and was used first for the Aqua Appia and the Anio Vetus, and afterwards by Nero. The existence of such a foss between the east end of the Cœlian Hill and the Cœliolum is denied by those who have not paid attention to the subject, and have not been into the gardens and vineyards to examine it; but the fact is a matter of demonstration. The tomb of the first century (miscalled the House of Verus, probably a tomb of the great Lateran family), being on the western bank of that fortress and the eastern bank of the foss, and the other tomb of the first century also, in the garden of what was the Museum of Campana (_under_ an arch that carries the modern road), on the western side of that great foss, are a demonstration that there was such a foss on the east side of the City of Servius Tullius, i.e. that the Cœliolum and Lateran did not form part of the City at that time. (See my chapter on the Tombs, and the photographs of these two tombs, 174 and 1942). The Arches of Nero remain on the Cœlian in many parts of the line, by the side of the road from the Lateran to S. Stefano Rotondo and the Navicella, with the arch of Dolabella, which was under the great reservoir of Nero, and formed the entrance of the Claudium. The Arches of Nero are faced with the finest brickwork in the world (ten bricks to the foot, as usual at that period, and are chosen as typical examples). This is well shewn in 78, and the internal construction of rubble, faced only with the fine brickwork, in 358. A line of these, shewing the picturesque effect, is shewn in 131 and 357. The aqueduct formed one of the usual angles between the Lateran and the arch at the west end of the Cœlian. It has been destroyed in this part; but this accounts for the arches being sometimes on one side of the road and sometimes on the other.