Cycled around spain abit, wouldn’t recommend it to be honest, at least from Biblao to Barcelona.
Its a very bike unfriendly country, you can’t even take your bike on most trains, I had to pack it into a box and put in on a coach with was a right pain in the arse.
Also 95% of spanish drivers are maniacs.
Recently went to Europe with my bike on the ferry (I was the only bike). It was pretty ace, cycled from Amsterdam to Bruges and was really lucky with the weather. I will add a page with travel advice/details.
The cycle lanes were excellent although I was surprised to find I prefer some English ways. I prefer on road cycle lanes where bikes are seen as being equal to cars. In Holland/Belgium they aim to separate the two. This means that cars have to give way to bikes or visa versa at junctions. Either is pretty irritating, time wasting and in my opinion dangerous. I think if drivers and cyclist are polite and considerate they can coexist well on all but the busiest speediest roads.
I was most impressed on the inter-city routes. Most of the major roads had an adjoining cycle lane. This is a area I think england is sadly lacking. Holland’s cycle network especially was a joy to travel along and fairly easy to navigate (with little or no preparations).