Here's an extract from the map so you can see what it's like.
Thick black lines are main lines, thin black lines are local and regional lines, red lines are special high-speed lines;
The green highlighted routes are scenic, yellow around the coastline indicates beaches;
Major mountain ranges, rivers & ferry routes are shown.
Reproduced with the permission.
This is an earlier edition of the map - the latest edition shows the high-speed Madrid-Barcelona line as completed, and shows the new Cordoba-Malaga high-speed line.