The Roman Map of Britain Viseranorum? Vederanorum? or Setantiorum (portus)? Skippool, Poulton-le-Fylde, Lancashire

Veteranorum (the second half of R&C 124) next
Setantiwn limhn Setantiorum portus, vars. Segantiwn Segantiorum, Gesantiwn Gesantiorum (Ptolemy II 3 2)

Margary 703 (ribchester-poluton le fylde) connects the previous entry, Ribchester, to the river Wyre Wir 12th c. Ekwall considered the river-name to be based on *ueis- found in Gaulish Visera, and W. gwyar 'blood'. Vetera- bears a strong resemblance to Visera written with a long s. Vedera also seems possible, see Vedra (Ptolemy II 3 4) - the Durham river Wear. Both the Cosmography's form and that of the Geography appear to be a genitive plural.

Ptolemy's Setantiorum portus has little place else to be but at the Wyre, if Seteia and Belisama represent the Mersey and the Ribble. To completely explain the form is impossible, but perhaps there was some borrowing from Seteia to restore a badly damaged entry.

Alternatively, Setantiorum can be resurrected from the Ravenna form. Veteranorum can be a mis-read  Vet'a- for Vetâ- (Vetera- for Vetan-), -norum for -tiorum, and V the product of a text divider ( | ) merging with a long s. 

Margary thought the ultimate destination of M703 to be Skippool (SD3640) which he considered suitable for a small harbor.

Tradition holds the proper name of Ribchester to be Bremetennacum Veteranorum. Richmond¹ explained it as the site of a veterans' colonia for imported Sarmatian troops.

1. Richmond, I.A. 'The Sarmatae, Bremetennacum Veteranorum and the Regio Bremetennacensis' JRS xxxv (1945) 15ff