which country schengen visa

I am from India and will be doing a cruise from Barcelona for 12 days going to Nice and Italy and returning to Barcelona. I would like to know which country should I apply for the schengen visa. I will be staying in Barcelona for 3 days prior to the cruise. so should I apply in spain or Italy?

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Normally you apply to the country you first visit. It doesn't have to be, but Spain is as simple as France or Italy.

A single-entry visa allows you to travel freely backwards & forwards between all Schengen countries.

But if at any time you visit a non-Schengen country you need a multi-entry visa in order to get back into a Schengen country.

Does your cruise visit Croatia or Montenegro or Albania or Turkey or Gibraltar or north Africa?

JB :)