Sintra

Sintra is a fairy-tale town of colorful palaces and misty forests, and the big budget win is that you reach it from Lisbon on a cheap commuter train, then spend most of the day without buying a single palace ticket. The whole UNESCO-listed historic center is free to wander, from the twin-chimneyed exterior of the National Palace on the main square to the steep little shopping lanes like Rua das Padarias and the shady Parque da Liberdade. The real money trap is that each palace charges its own entry fee, so pick one interior at most and let the misty hillside trails, free public miradouros, and the views toward Pena Palace carry the rest of the day. For a free coastal add-on, Cabo da Roca, the westernmost point of mainland Europe, sits within the same Sintra-Cascais nature park and costs nothing but the bus or drive out. Tickets and crowds both ease outside the peak summer months, so a spring or autumn visit is kinder on both your budget and the long palace queues. From here you can pair Sintra with Cascais on the coast or loop back to Lisbon on the same train line.