After eating the Paschal meal with his disciples in Jerusalem (Luke 22:10), Jesus would have set out with them to climb the Mount of Olives to go back to Bethany where they will spend the night.

 JN 18:1 When he had finished praying, Jesus left with his disciples and crossed the Kidron Valley. On the other side there was an olive grove, and he and his disciples went into it. (John 18:1)

  MK 14:26 When they had sung a hymn, they went out to the Mount of Olives.

The 'garden' of Gethsemane was not actually a garden but an olive grove.

MK 14:32 They went to a place called Gethsemane, and Jesus said to his disciples, "Sit here while I pray." 33 He took Peter, James and John along with him, and he began to be deeply distressed and troubled. 34 "My soul is overwhelmed with sorrow to the point of death," he said to them. "Stay here and keep watch." 


 

could these be descendent of the olive trees under which Jesus prayed

 These trees have an appearance of twisting on its trunk as if having suffered from severe agony.

 
 
 
  This is a sacred place where a momentous decision was made. Jesus has to make a decision. Obey God the Father which may lead to humiliation, torture and a horrific death, or walk about 10 minutes up the hill and escape into the desert before Judas and the soldiers come for him. I believe that Jesus is truly human, truly God. Yet, at this moment in time, Jesus God incarnate is human having set aside his Godhood. Otherwise if he is also fully God, then there is no decision to be made. It would have been an act rather than a struggle. Jesus struggled until his sweats were his blood.