Well, They are actually on a field trip, but instead of taking bus, they are all walking. I only discovered that they are all heading towards the mountain when I started discovering the churches in the eastern part of Metro Manila. Yes, during Maundy Thursday, pilgrims are all heading to Antipolo - to the National Shrine of Our Lady of Peace and Good Voyage or Immaculate Conception Parish and then take on separate routes as they leave the place on the morning of Good Friday.
If you'll have a chance to visit the churches in the eastern part of Metro Manila - churches in Pasig, Mandaluyong, some parts of Quezon City and Makati - on Maundy Thursday, you'll notice this great number of people walking barefoot. There are some who are wearing uniformed shirts and yes again, they are all heading to one direction. Mostly youth, these people are doing an old tradition of hiking up to Antipolo for the annual pilgrimage to Lady of Peace and Good Voyage .
If I'm not mistaken, my first and last pilgrimage to the Church of Antipolo was when I was still in Primary School. I was so young then and I was with my old aunts and old neighbors, so we didn't walk, rather we hired a jeepney to take us up to Antipolo.