Sintra, Portugal, a picturesque city 15 miles outside of Lisbon in the Sintra Mountains, is home to numerous palaces, villas, mansions, castles, and churches.

The most stunning of the sights in Sintra is the Pena National Palace, built in 1840 according to the exacting specifications of King Ferdinand II, who wanted the palace to be a melting pot of architectural styles and colors.

The palace is said to have inspired King Ludwig II's German castle, Neuschwanstein, which inspired Walt Disney's castle at Disneyland.

Though the palace and the surrounding grounds are undoubtedly crowded with tourists in the summer, it is a can't-miss, dreamy sight that visitors are unlikely to forget.

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I almost didn't go.

After spending several weeks running around Lisbon, Porto, the sun-drenched beach region of Algarve, and everywhere in between, I thought: Why not relax on my last day in Portugal and avoid a place often described as "Disneyland for adults"?

What a mistake that would've been.

Only 15 miles from Lisbon, Sintra is about as fairy-tale Portugal as it gets. Designated as a Unesco World Heritage Site, the picturesque city is on the Portuguese Riviera and among the Sintra Mountains, a verdant range dense with pines, oaks, and wildlife. It's long been known as the setting of several myths, legends, and supernatural happenings in Portugal.

The otherworldly air is enhanced by the numerous palaces, villas, mansions, churches, and castles ensconced in the forested mountain peaks.

While there are more than half a dozen sites to visit, the most stunning two, in my opinion, are the Pena National Palace and the Castle of the Moors. The architectural feats — built in 1840 and the ninth century, respectively — best exhibit how Sintra has been a romantic destination throughout the ages.

The Pena Palace is made of dreams. At the top of a hill to be visible in every direction, and often enveloped in fog, the palace is a tapestry of colors and styles ranging from Romantic to Islamic to Gothic, surrounded by 500 acres of winding paths, gardens, and exotic trees.

You're likely to feel as if you are walking into a magical kingdom — I certainly did on my recent visit to the palace and the surrounding castles and gardens in Sintra. Here's what it was like.