Portugal trip suggestions

Two weeks is not too much time, you could do that in Lisbon and Porto alone. Stick with your plan, if you find yourself getting bored, then there is plenty of beach to sit on, and other smaller towns, near Faro; and the Douro valley near Porto to look at the vineyards.

Hello, 2 weeks is certainly enough - depends how busy you like it and where all you want to go. check the other posts in the portugal section below for itinerary ideas from newbies like me and more experienced folks like Kathyrn who live there. we have commented in various recent posts from this month.

4-5 days in Lisbon area (lisbon, belem, sintra, cascais, evora overnight if you wish. Lisbon is fun, lots of young folks, good food and people, good weather, not expensive)
2-4 days in Porto area including Duoro
some time in Faro (i did not go here as water was cold in early april)
you may still have time for Spain (barcelona and madrid/toledo will be cooler, have a large young population presence including american, canadian and british visitors - and of course, hispanics)
you could save a bit by booking at good hostels - private rooms if you'd prefer.
can book Spain flights last minute - there are many from Lisbon to Madrid/Barca and they are not expensive (30-80$)
yes, Andalucia will be hot. its seems to be a fantastic area of Spain to visit and I have planned it for future.

P.S. most folks on this forum like it slower - "live like the Europeans" which I want to do someday. but I have limited vacation and budget and I am in the "sightseeing" phase of my life. from my 3 trips to Europe in the past 6 months, I have learned that 3 full days in a city is enough to get a good flavor and do the major activities and sights without much rushing - again depends on your style and needs. Lisbon is interesting because Sintra/Cascais, and Evora are all accessible as day trips from here. Evora comes highly recommended - even as as an overnight trip but I had not planned for it.

Two weeks are enough -- because of work obligations, most of my international trips over the past 20 years have been two weeks or less, yet I've enjoyed these trips thoroughly -- including my one (so far) trip to Portugal in 2017. I think your four chosen Portugal cities are sufficient for two weeks (of those four I visited Lisbon and Coimbra and loved both). But before taking my advice, note that my style may be a bit different from most; I prefer to spend my two weeks "getting into" two or three selected historic cities, as distinct from dashing about -- a night here, a day trip there -- in an effort to see all the "must-sees." But if your travel style leans more towards the latter, you may still be able to squeeze in a fifth or even a sixth city or town as well. (Though maybe not as far afield as Cordoba or Granada -- they're great places to visit, but maybe not on a two-week trip that focuses on Portugal.)

I agree you can find lots to do in Portugal for two weeks. I'm not sure what accommodations you are thinking of, but Portugal has a number of great hostels to stay in. Our son traveled with friends in Portugal and enjoyed numerous ones. My husband and I ended up in a hostel in Coimbra for a night ( did get our own room) and again had a great stay.
It will be warm though, and not all of the cheaper ones have air conditioning. I would suggest splurging on AC much of the time.

Don’t try to do Spain. It’s simply too hot in the summer, plus there is more than enough in Portugal to fill your time. Evora is great but it, too will be very hot.

There are a number of areas in Lisbon (and likely Porto) that have a concentration of younger people with a lot of night life. Plus, so many beaches! Don’t think of beaches only in the Algarve. BTW, the beaches there will be predominantly British tourists.

Once you get a better idea of where you will be and have specific questions, I’m happy to help - if I can.

My understanding is that getting to Spain from Portugal and back by train is really difficult, you probably won't want to rent a car (and there's additional charges for going to Spain with that, too) so your only option would be coach bus. I'd stick to Portugal. As others have said there's plenty to entertain you in those 4 places alone, but with 2 weeks and being young you could venture to a few other places provided they're well connected by train - you can save money on train tickets by purchasing now, by the way!

Lisbon seems like a good hostel city based on my own search for accommodations (I've aged out of those types of situations) and it's a great way to meet other solo travelers and make friends. I'd look into that but book soon. The taxi drivers I spoke with in Portugal last week said that tourism this year is above 2019 which was a record year. The good and popular stuff is booking up. Make finalizing your itinerary a top priority and then book. Based on just one day/night in Lisbon last week, I realized I could be happy there (as a fairly active traveler) for a week and am already slightly regretting that I only have 3 nights there this week. I know I'll be back for sure. You can read about my brief impressions at my trip report here. I'm not visiting Sintra either on this trip because I just don't feel I have enough time to do Lisbon proper yet.

As for the rest of your itinerary, I'd ask if you had a reason for Faro (aside from the fact that it's somewhat known) as a base in the Algarve. Most of my research has pointed me to Lagos which is also on a train line and seems to have plenty to do - the only reason I'm not staying there is we want a more relaxed beach trip and Lagos seems a bit too hopping for that, but we're certainly going to make a day trip there. It seems to attract an anglophone crowd in your age range.