Unfortunately, Portugal doesn't have too much quality. And a lot of it is now flying away, since a great part of the young people is chosing emigration.
In the southern half of Portugal, the genetic ancestry is more moorish (Arab), sephardic (jewish) and also African. In the north, there is more celtic and nordic genetic ancestry.
So, you will naturally see more beautiful girls in the northwestern part of Portugal. In
Douro Litoral and
Minho regions mainly. Thus, Porto, Gaia, Braga, Guimarães, Barcelos, Viana do Castelo are some of the cities where you will find better quality.
I found Pepini's portrait particularly accurate in stating that in Portugal the higher is the social status the higher is the quality (i.e. in terms of beauty, because as you may guess rich girls tend to have more futile and spoiled personalities, and maybe this is more noticeable in Portugal since the differences between social classes are big).
He is also pretty much correct saying that game/relationships in Portugal is a very social-circles oriented thing. Quite so.
Regarding you, naughty foreigners who come in to short stays and hence search easier sex and one night stands, I'd say your best chances will be in Coimbra (see the
NY Times report). Coimbra is almost exclusively a student town. It has about 100.000 people and it has one of the oldest universities in the world. So, thousands of young students living away from their parents plus the college partying scene and lots of alcohol will increase your chances of getting laid. Thursday is when most students go out at night since a lot of them return to their families' houses on weekends. There are two great annual student fests with some particular old traditions associated: the "Latada" (usually in late October) and the "Queima das Fitas" (in early May). Each one of this fests lasts for a week and all students are partying in the streets, bars and clubs and there is also an additional increment of more students and other young people coming from other parts of the country.
You may also take a look at Braga. Braga has a 150.000 population, also has an university but doesn't have as many students as Coimbra, Lisbon or Porto. But as an advantadge there are lots of young people there, it is indeed statistically one the of the youngest cities in Europe (i.e. higher percentage of young people within its population). Check out Aveiro too.
Lisbon and Porto are the two major cities and also have bigger young student population. The problem is that, in comparison to Coimbra or even Braga, that Lisbon and Porto's students are more sprawled within the cities and without a local guide/wingman the places where they hang out can be harder to spot or you may find that bars and clubs have less students in weekends since those who are from other places usually return to their homes on weekends, as I mentioned before.
I'm not from Lisbon and I never went out at nigh in Lisbon, but I know the city and I know the nightlife is mainly concentrated in two zones:
- Bairro Alto (all kinds of venues in narrow steep old streets where everybody is speaking and drinking mostly out in the street since the bars are tiny and expensive)
- Docas/ Santos /Cais do Sodré zone (close to the port of Lisbon, it was a place of prostitutes and drunk sailors in the old days, but became a zone of trendy bars and clubs in the latest years).
I think Pepini had already said the essential about Portugal and Lisbon in particular.