This is from Johnnie Walker's guide:
From the Praza do Obradoiro in Santiago and with your back to the cathedral, pass in front of the Hostal de la Reyes Católicos (on your R), go down the slope in front of its garage (this is the Costa do Cristo), then down some steps and along the Rúa das Hortas ahead. (Many of the older houses on this street have scallop shells in the stone lintels above the doors). Veer R at the end into Rúa Campo das Hortas and turn L at traffic lights to cross Rúa do Pombal via pedestrian crossing. Continue ahead down Rúa do Cruceiro do Gaio (the first of two streets in front of you) and then along the Rúa da Poza de Bar (unnamed at start); this then becomes the Rúa de San Lourenzo.
At the Carballeira de San Lourenzo (a small, shady park with seats, a fountain and a lot of old oak trees) there is the first camino tile and clear yellow arrows. Here you can either:
a) Keep Straight On ahead to visit the (former Franciscan monastery) church of San Lourenzo de Trasouto (normal visiting hours Tuesdays and Thursdays 11-1 & 4.30-6-30, otherwise open at Mass times) and then retrace your steps, crossing the Carballeira diagonally alongside the monastery garden wall (on the Costa do Cano) and veering L to pick up the camino ahead or:
b) turn R (coming from the cathedral) down the Roblada de San Lourenzo (signposted “Sanatorio”). Shortly afterwards veer L down a cement road (Corredoira dos Muiños) leading you downhill to cross the bridge over the Río Sarela in hamlet of Ponte Sarela.
Or - just follow other pilgrims also walking to Fistera!
. I know the route starts at the Cathedral........ ? Thanks in advance to anyone out there 
