[326] e.g. Friedberg has an area of (roughly) 10 acres, Okarben of 14, Heddernheim of 13, and Kesselstadt of 35. A cohort of 500 infantry was usually allowed about 5 acres.
[327] See Macdonald, The Roman forts at Barr Hill, pp. 11-15; Curle, A Roman Frontier-post, pp. 29, 349.
[328] xi. 6344 ‘P. Cornelio P. f. Sab(atina) Cicatriculae prim(o) pil(o) bis, praefect(o) equit(um), praef(ecto) clas(sis), praef(ecto) cohortium quattuor civium Romanor(um) in Hispania, trib(uno) mil(itum)’.
[329] iii. 14147².
[330] W. D. Z. xxi. 186, where this theory of the first-century frontier system is further developed.
[331] See Pelham, op. cit., p. 199. The forts on the North British frontier range in area from 2½ to 5½ acres, the largest (Amboglanna) being designed to hold a cohors miliaria peditata. The German forts seem to have been on a rather larger scale, and ran up to 15 acres, which is the area allowed at Aalen to an ala miliaria. It is not meant, of course, that forts of this type did not exist in the first century, but it was not until the reign of Hadrian that the dispersion of the auxilia in separate units was adopted as a general policy.
[332] Cf. iii. 3385 ‘(Commodus) ripam omnem burgis a solo extructis item praesidis per loca opportuna ad clandestinos latrunculorum transitus oppositis munivit’. This is from the Danube frontier.
[333] Historia Augusta, Vita Hadriani, 12 ‘In plurimis locis in quibus barbari non fluminibus sed limitibus dividuntur, stipitibus magnis in modum muralis saepis funditus iactis atque conexis barbaros separavit’.
[334] The best recent account of this frontier in English is Pelham’s essay, ‘The Roman Frontier in Germany,’ in the work already cited.
[335] Recent researches have, however, made it very doubtful whether a turf wall ever preceded the stone wall along the whole line.