According to Christian tradition, Jesus was executed in AD 33 just outside the walls of Jerusalem on a hill called Golgotha (Greek) or Calvary (Latin).
In 135 Hadrian, Roman ruler and devout Olympian that he was, had a temple dedicated to Jupiter built on the site of the old Jewish temple and a temple dedicated to Venus built on Golgotha. To provide an adequately strong and flat foundation for the temple on hilly Golgotha, and to thoroughly cover any visual reminders of Christian significance, Hadrian had tons of rock and dirt brought to the site.