Sorry no ideas for voluntary work, but Newcastle is a wonderful city. I especially like the river area, with the 7 bridges.
Two of my aunties lived in Gosforth , but I haven't been there recently. The Town Moor is nearby.
We live just south of the Tyne now, but easy access to Newcastle.
Excellent public transport and short journey to the coast.
And I've just remembered - eldest daughter did teacher training in Newcastle and went to classes for flamenco dancing somewhere in town.
As to language, you might need lessons in Geordie as well as Spanish.
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