teen ▁ ▁tren ch ▁gra ves ▁without ▁coff ins ▁in ▁a ▁former ▁corn ▁field , ▁so ▁it ▁is ▁unknown ▁exactly ▁how ▁many ▁prisoners ▁were ▁buried ▁there . ▁ 1 1 , 7 0 0 ▁is ▁the ▁generally ▁accepted ▁number ▁which ▁is ▁shown ▁on ▁the ▁monument , ▁but ▁research ▁has ▁shown ▁the ▁number ▁to ▁be ▁close ▁to ▁ 3 8 0 0 . ▁ ▁The ▁f ence ▁St on eman ▁had ▁ordered ▁be ▁built ▁around ▁the ▁tren ches ▁was ▁later ▁replaced ▁with ▁a ▁stone ▁wall . ▁After ▁the ▁American ▁Civil ▁War , ▁the ▁c emetery ▁officially ▁became ▁a ▁National ▁C emetery ▁and ▁had ▁remains ▁from ▁other ▁c em eter ies ▁around ▁the ▁area ▁transferred ▁to ▁it . ▁ ▁Sal is bury ▁National ▁C emetery ▁was ▁listed ▁on ▁the ▁National ▁Register ▁of ▁Historic ▁Places ▁in ▁ 1 9 9 9 . ▁ ▁By ▁ 1 9 9 4 ▁the ▁c emetery ▁was ▁expected ▁to ▁fill ▁up ▁by ▁ 1 9 9 7 , ▁with ▁no ▁more ▁bur ial s ▁other ▁than ▁sp ouses ▁of ▁those ▁already ▁there . ▁Despite ▁add itions ▁in ▁ 1 9 7 6 , ▁ 1 9 8 5 ▁and ▁ 1 9 9 5 ▁that ▁gave ▁the ▁c emetery ▁a ▁total ▁of ▁ 1 2 . 5 ▁acres , ▁and ▁ 5 8 0 0 ▁buried ▁at ▁the ▁c emetery ▁already , ▁it ▁was ▁later ▁predicted ▁that ▁by ▁the ▁end ▁of ▁ 1 9 9 9 , ▁the ▁c emetery ▁would ▁have ▁no ▁more ▁room . ▁Representatives ▁of ▁the ▁c