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Pilgrim’s reception office of Santiago de Compostela. Cathedral of Santiago: services, opening hours, where we are, ...
From the drop-down menu select ‘register’. Select ‘single’ and for unknown reasons check ‘create a group’. Do this for each of you individually.
Or - which I’ve not personally done - you could select ‘group’ and apply once for all of you; but with different starting points for the certificate of distance that may cause confusion.
Apply for a QR code when you get to Santiago as you’ll go in the queue straight away. In the case of the one who, for this purpose, started in Leon their distance certificate will reflect just that. The compostella only requires the last 100km (on foot) and does not show the distance.
The distance certificate - which is different and additional to the Compostella - is optional and costs a few euros.