Is the Algarve worth adding to a Portugal itinerary?
The Algarve is worth adding if you want beach and coast time. Add it to a short city-and-food trip just because it is famous, and Portugal starts becoming a transfer exercise with better cliffs.
Answer
The Algarve is beautiful in a very different register from Lisbon or Porto: cliffs, coves, sea air, resort towns, fishing-town remnants and long summer evenings. But it is not automatically the right ending to every Portugal itinerary. If your trip is already full of cities, wine, food and train travel, the southbound detour can cost more energy than it returns. If you want a slower coast break, it can be the release valve the route needs. Be honest about the holiday you are building. Portugal does not require a beach chapter to feel complete, and the Algarve is best when it is chosen, not appended.