Garmin sell satnavs with different combinations of maps, I guess in your case you will have either UK. or Europe maps, there are a couple of ways to find out, you can check the map name in the Nuvi menus e.g. Settings >> Map & Vehicle >> myMaps >> CN Europe NTU
You can also check the map for certain areas with . . . 'View Map' then zoom out with the '-' icon until you can see say Spain, then zoom in keeping Spain in the center on the screen, if you can see non-main roads in this area you will have the Europe version
Note :- your Nuvi may also have a general 'World Map' where a zoomed out view will show other continents, however if you zoom in on these areas, you will only get main roads, there will be no 'fine detail'