Portugal is home to some of the most spectacular castles in Europe, each with its own unique history and architectural style. Here are some of the most interesting castles in Portugal to visit:

Castle of Evoramonte: Located near the town of Estremoz, this castle was built in the 16th century and is considered one of the most beautiful in the region. It has a rectangular shape with four towers and a beautiful, sweepeing view over the Alentejo countryside.

Castle of Guimarães (Minho)- Considered the birthplace of Portugal, the Castle of Guimarães dates back to the 10th century and played an important role in the country's history. It's a must-visit for history buffs and those interested in medieval architecture.

Castle of São Jorge (Lisbon) - Perched on a hill overlooking Lisbon, the Castle of São Jorge offers stunning views of the city and the Tejo River. Dating back to the 11th century, it is one of the most popular tourist attractions in Lisbon. But few know it was totally rebuilt in 1940.

Castle of the Moors (Sintra) - Also located in Sintra, the Castle of the Moors is a medieval fortress built during the 8th and 9th centuries by the Moors. It offers stunning views of the surrounding landscape and is a great place to learn about Portugal's Islamic history.

Castle of Monsaraz: Located in the hilltop village of Monsaraz, this castle was built in the 14th century and has a unique circular shape. It is a great example of medieval military architecture and offers stunning views over the Alqueva Lake.

Almourol Castle - Situated on a small island in the Tejo River, the Almourol Castle is one of the most unique and romantic castles in Portugal. Dating back to the 12th century, it can only be reached by boat and offers stunning views of the river and surrounding countryside.

Tomar Castle - Home to the famous Knights Templar, the Tomar Castle is a testament to Portugal's medieval history. It features impressive Gothic architecture and is a great place to learn about the country's religious and military past.

Castle of Marvão: This medieval castle, located in the town of Marvão, was built in the 13th century and is perched on a hilltop with a breathtaking view of the surrounding countryside. It is considered one of the most impressive castles in Portugal.

Castle of Vila Viçosa: This castle, located in the town of Vila Viçosa, was built in the 14th century and underwent several renovations in the 16th century. It has a rectangular shape with four towers and is considered one of the most important castles in the region, as it was built by the family that would become the last dynasty of Portuguese royals.

These are just some of the best castles in Portugal to visit, but there are many more to explore and discover throughout the country.