My wife & I did a monster 15 consecutive weeks in Europe last year ... a month in Italy, a month in Spain, 3 weeks in France, and the rest of the trip blitzing other European highlights like Amsterdam, Bruges, Prague, Krakow, Budapest, Vienna, Munich, scenic Swiss trains etc. ... And for me, Spain's the #1 place in Europe i'd return to.
But we escape the Canadian winters every year to live in Colombia. And so Medellin (where I am now) is my favourite place to be for at least Dec, Jan, & Feb.