Cave dwelling was common in Bethlehem and even today many very old houses are actually built in front of caves. In the second century Justin and the Protoevangelicum of James speak of the cave in which Jesus was born and there is a network of caves under the Church of the Nativity. Pre Constantinium locations of sacred site have a very strong claim to validity (more so than those of the fourth century) due to tradition and memory of those who passed the sacred locations on to their descendants. St. Helena dedicated the first church on 31 May 339 and the Apse was was sited directly over the cave which you will visit. The only visible element of this church is a pavement of the nave 50 cm below the level of the new nave. Alterations and modifications would have certainly altered the interior, but it is thought that given the slope of the hill, the natural entrance was on the north or east. Given this, I believe that you will truly enter the birthplace of Our Lord.
Regarding the Church of the Holy Sepulchre: In the first century the location was a disused quarry outside the city walls. Typical 1C tombs were cut into the walls, indeed you can enter two in the church itself today. The Jerusalem community held liturgical celebrations until AD66 and even when it was inside subsequently built walls (AD41) it was never built over until Hadrian filled it in to erect a temple to Aphrodite (presumably to stop Christians from gathering there) In doing so, I believe that in doing this he “monumentalised” the site of the Crucifixion and Resurrection. Certainly St. Helen went to the site after researching with local Christians and Eusabius says in the "Life of Constantine that when the pagan structure was demolished and the top level of earth removed "the venerable and most holy memorial of the Saviour’s resurrection, beyond all our hopes, came into view " Constantine’s church was started there in AD326 the rest is history, as they say! Going to that place, touching the rock of Golgotha and entering the edicule over the site of Our Lord’s Tomb was perhaps the most powerful moment of my life. My wife and I spent 7 days in Jerusalem and visited that place every single day. I would return tomorrow if I could. I hope you have a similar life enhancing pilgrimage.
