Tips for visiting Portugal from early to mid-Mach

I was in Portugal last March about that same time. We had 'mixed' weather. Over our nine days we had two total washout days and several more that were cool and cloudy. But last spring all of Europe (and much of the eastern US) was having horrible weather so maybe other years it would be better. But I wouldn't count on gorgeous weather. I read a lot of trip reports in planning for that trip and it seems things don't get reliably "nice" till around May. We choose to do Lisbon and south rather than north in hopes of better weather.

Here is the trip report I wrote about that trip https://www.fodors.com/community/europe/6-days-on-the-algarve-and-3-in-lisbon-march-2018-a-1651723/page2/

My photos are here: https://andiamo.zenfolio.com/f334280890

In terms of time - we spent only 3 days in Lisbon on that trip but I had been before. I would consider that an absolute minimum. My previous trip we spent 6 days and had no trouble filling it up. There are numerous day trips. I've not been to Porto but on my first trip to Portugal we went as far as Combria (also Evora, Maovra, etc.) and that took another 6 days so I think you would really be rushing to fit in Spain. Although you might find better weather in Salamanca. I've only been there in summer but it had beautiful hot sunny weather at that time of year. Even in summer Santiago was rainy (forecast every day is "mist" which is what it gets, not really rain but wet, supposedly the rainiest city in Spain).

We went to Portugal November 18-December 2, 2018, so I can't help you with mid-March. We were in Lisbon for two days, 1.5 days in Sintra, 1.5 days in Evora, traveled from Evora to Coimbra via stops in Obidos, Alcobaca and Batalha, two nights (one full day) in Coimbra, then drove to Porto via Guimares and spent two nights (one full day) in Porto.

We are out the door by 9 a.m. (or as soon as our B&B's serve breakfast) and then into the hotel by 11 p.m. type travelers. We also tallied between 21,000-35,000 steps each day of our trip, so we were pretty constantly moving.

Because we were limited in time, (both in terms of days and due to "winter hours" at many sites) and because we've traveled to France, Spain and Italy, we were picky about what we paid to enter. For instance, we didn't pay to enter the Lisbon Castle, because most reviews online said "the view was great!" but were less than enthusiastic on the castle itself. Knowing we were going to the Moorish Castle in Sintra, and the castles in Obidos and Guimares, I didn't want to pay for Lisbon Castle and spend my time on it. Plus, you can get amazing views of Lisbon from other vantage points around the city.

I thought two days in Lisbon was plenty. We spent one full day doing the RS walking tours and wandering the city, then the next day we went to Belem. I thought the cloisters at Belem were a total disappointment, particularly once compared to the cloisters in other cities in Portugal. Belem offers no audioguide (despite what the RS book says) and hardly any signboards, so there is no explanation for what you are looking at or its historical relevance. I would skip these cloisters and find another with better information. The Cloisters at Batalha were much more informative.

I would highly recommend Sintra, but I think the typical day-trip to Sintra is not enough. We were at Pena Palace when it opened at 10 a.m., stayed there until 1 p.m. (including a walk through the park), went to Moorish Castle from 1-2:30, then walked down the Via Sassetti, arriving at the National Palace at 4 p.m. This was a full, relatively hard day. It didn't help that it was raining buckets on us, so we were soaked from the Moorish Castle onward. However, there is no way to then fit in a stop at Quinta de Regalaria. We did that the next day and spent a full three hours there. It was definitely one of the highlights of our trip.

I also thought one day in Porto was enough. We did the RS walking tour, popped into churches, walked miles and did a port tasting in Gaia. Again, we were picky about what we paid to enter. For instance, even thought the Sao Francisco church in Porto is a *** per RS, we didn't pay to go in. First, it was 7E each for admission, which seemed very steep (we used RS 2017 Portugal book (the newest available) and found prices to be significantly higher than the book stated, and not as many audioguides available as RS said there would be.) and by that point, we'd seen so many beautiful churches that it didn't seem necessary to pay that amount to see one more.

I would suggest renting a car. Driving in Portugal is easy, and while the train to Sintra runs often, the trains to other cities don't seem as regular. The Portuguese that we talked with who asked about our plans, also indicated approval with renting a car with most saying its just too time consuming to use trains. Plus, that lets you see additional cities/sites on your way to your overnight location.

Hard to give good advice not knowing your interests. In my opinion, you could spend the whole time in Lisbon and not run out of interesting things to do. I just spent two weeks in the Lisbon area (i have been there many times), and could have stayed longer.
Porto is a smaller city, but quite interesting. There are many good day trips from both Lisbon and Porto.
Regarding weather, it gets wetter and colder as you go north. Portugal gets greener and in my opinion prettier as you go north, the the far north, Minho, is my favorite part of the country. Having said that, the winter weather up there is cold and wet. The up side for that time of year is that there are far fewer tourists.

Santiago de Compostela over Salamanca for sure. I would start in Lisbon/Belém/Sintra ;5 days without a car then trainCP to Porto for 2-3 nights pick up a car, drive to Santiago then back to Porto or Lisbon if the drop off fees are reasonable.
Weather can be cool & rainy especially in northern Spain, but if the sun is out very pleasant.

With your timeframe, I would stick to Portugal, as there is so much to see there.

This year, early March was unusually wet. There are many websites denoting average weather, but these wouldn’t have been much use this year, with the topsy turvy weather we have experienced.

1. “Is early/mid March a good time to travel?” Compared to say May/June there - no, as the weather will be cooler and wetter. Compared to say visiting northern Spain or the UK at that time of year? Yes, as the weather will be better in Portugal.

2. Lisbon with day trips to Cascais and Sintra merits 5 full days (or longer). Hire a car at the end of your Lisbon stay. Evora is worth an overnight stay or 2. There are many places worth seeing over several days on the drive to Porto such as Obidos, Tomar, Alcobaca, Coimbra, Batalha, Aveiro etc. From Porto, you could see the Douro.

3. If you just want to see Lisbon and Porto, then the train is best. If you want to visit places in between, a car will give you the most flexibility. Car hire in the winter is cheap in Portugal and driving (other than in Lisbon) isn’t difficult.