You can purchase a credential online from Ivar in this forum, and have it mailed to you worldwide. Minimum 2 euro + 4 euro shipping ( 2-3 week delivery ) for DHL 2 day delivery it is more expensive, about 12 euros.
It is about 90km from Santiago to Finisterre, so walk at what ever pace is comfortable. Some people do 30km a day or more, some people only do 20km a day. So 3 or 4 days would get you there. Remember, it is not a race.
This site is run by Ivar at in Santiago de Compostela.
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