Giving up residency

I have been resident in Spain for the past 3 years but am returning to the UK for at least 3 years at the end of this month.  I intend to keep my property here as a holiday home.

I have the old style residency card and would like to know whether I have to return this to the extranjeros department from where I received it or whether I can just cut it up and dispose of it. 

Also, which other authorities need to be informed of my departure?

Any info much appreciated

Hiemmerson:

You need to fill in the EX-16 form to declare before the State that you are not longer a resident in Spain. Need to bring your passport, your residency document and pay the corresponding fees. You need to go in person.

Best regards,

Maria L. de Castro