Solo 10 day travel to Portugal

Hi everyone,

I’m planning a solo 10-day trip to Portugal in late March through early April and would love some advice from people who’ve been there or live there.

I’m looking for recommendations on:

Must-visit cities and towns

Hidden gems or underrated spots

Scenic train routes vs. renting a car

Whether public transport is sufficient or if a rental car is worth it

Hotel vs. Airbnb (and specific area recommendations if possible)

Food spots I shouldn’t miss

Day trips that are realistic and worth it

I enjoy a mix of culture, scenery, good food, some walking/exploring, and maybe a little relaxation. Not big on nightlife, but I do appreciate good atmosphere.