This half-day experience takes in two of the most iconic sights in Cartagena. Located just outside the historic old town, the imposing San Felipe de Barajas fortress is one of the city's most distinctive landmarks and is a formidable example of military might and architecture. Rising above the skyline, from this dominant vantage point the Spanish kept watch over the entrances to the city both by land and sea. San Felipe is the largest Spanish-built fortification in the New World, and along with the ramparts and stone walls was part of the city's defence against marauding pirates. Built on top of the San Lázaro hill, construction began in 1536 and continued for some 200 years. Underneath this amazing structure is a labyrinth of tunnels, many of which are still accessible. The sun-soaked fortifications are a living breathing history book, steeped with tales of old. The La Popa Convent sits in a privileged position, and is the highest landmark in the city. The convent started life as a humble and modest wooden chapel in the early 1600s but was later fortified and expanded to its current majesty. The cool, leafy, flower-filled courtyard and patio lead out to a viewing platform. From here there are panoramic vistas that stretch out over the city, old town, the bay of Cartagena, and the Caribbean Sea beyond. Inside the small chapel is the immaculate gold-plated and carved alter and ornate decoration dedicated to the "Virgin de la Candelaria", patron saint of the city. The convent still plays an important role in the life of the city's Catholics and is often full to bursting on religious holidays.