in spain you must have passport, licence and all bike doc's with you every time you ride,
if you get stopped by the police you pay the fine on the spot they will take you to cash point, or they impound your bike till you do pay,
as said spare bulds are leagal requirement over there,
oh something really silly over there they only stop for red zebra crossings not for the black and white one's we have
they recomend that you ware a HI-VI when riding but they dont enforce it,

have fun, i did ;D ;D

how are you getting from uk to spain???