Traveling in Spain I noticed that it is actually very hard to order apple juice in a normal restaurant.
However you can buy some apples or apple juice in supermarkets.
Why would that be?
In Spain apple juice is not as common as some other juices, but it is not the only one, in particular cranberry juice is also hard to find. Spain has always been a big producer of oranges, and the provinces of Valencia and Seville in the south of the country are particularly renowned for the fruit.
So it's no surprise that orange juice is common and popular.
You will find that most apple orchards tend to be in the north in provinces like Asturias, and most apples that are not produced for eating will be made into cider.
However there is one location that will I'm sure please you that you can almost always find apple juice in Spain: McDonald's.