Absolutely! Exploring Portugal's gems like Évora, Coimbra, Sintra, and Porto is quite the adventure. Here are some tips to help make your journey more convenient:

Best Time to Visit:
The best time to visit these cities in Portugal is during the spring (March-May) or fall (September-October) when the temperatures are pleasant, and there are fewer tourists.

Route and Accessibility
You can start your journey from Porto, then travel to Coimbra, followed by Évora and end your trip at Sintra, which is close to Lisbon. The train network in Portugal is extensive and reliable, making it an easy option for traveling between these cities.

Altitude and Acclimatization:
These cities are at low altitude and are near coastal areas so there should not be any issues related to acclimatization. However, Porto and Sintra have a lot of uphill walking, so remain hydrated and take it easy if you find the climbs tiring.

Accommodation and Booking:
There are various types of accommodations available in these cities, ranging from budget hostels to luxury resorts. Be sure to book your accommodations well in advance, especially if you're visiting during the peak season.

Clothing and Essentials:
Pack according to the season of your visit. Light, breathable clothes for summer, warmer clothes for winter, and don’t forget a good pair of comfortable walking shoes as you'll be exploring a lot of historic sites and cobblestone streets.

Health and Safety:
Overall, Portugal enjoys a safe environment, but basic precaution like not leaving your belongings unattended or avoiding deserted areas at night still apply. Also, keep a mini first-aid kit handy.

Local Etiquette and Respect:
Portugal is a culturally rich country with a lot of history. Always respect local traditions, and while visiting any religious or sacred sites, dress modestly. Always use a few common Portuguese phrases; it's appreciated by locals.