Crucifixion was a very common capital punishment in ancient Rome. After the Roman army put down the gladiator's War led by Spartacus, some 6,000 survivors were crucified along the highway from Rome to Capua.
Concerning Jesus' crucifixion.. The garden tomb (Gordon's Calvary) is located At Golgotha (the place of the skull),
directly below where Jesus was crucified..the top of the hill being bare rock.
"Infidels" can no longer go there, because it is a Muslim cemetery..but some who have been there in the past,
say there were holes in the rock above the tomb, that Romans carved as "sockets" for crosses.
According to Jewish law at the time..crucifixions could no be carried out within the city of Jerusalem. At that time, Golgotha was immediately outside those walls.
Below, see Golgotha and the garden tomb below.