My wife and I spent our summer vacation in Lisbon, Portugal, a soulful European capital with immediate charms and a deeper beauty that must be sought out. Once the launch pad for many voyages of discovery, Lisbon was the first true world city, the capital of an empire that spread over all continents from South America to Asia. We also took a day trip to Sintra, a UNESCO World Heritage Site known for its fairytale castles and palaces, and Cabo da Roca, the westernmost point of mainland Europe with stunning views of the Atlantic Ocean.