Use promo code "TZOOPORT" to save on this 6-night Portugal vacation exploring Porto and Lisbon. Spend three nights in Porto, where you can stroll along the Douro River, admire the Dom Luís I Bridge, and sample the region's famous port wine. Then take an included train ride to Lisbon for three nights, where you can ride the iconic Tram 28, visit Belém Tower, and explore the colorful Alfama district. You can also take an optional day trip to Sintra to see its picturesque palaces. The package inc