With its robust granite architecture and commercial disposition, Oporto, Portugal's second city, rewards visitors with a very different experience to that of the capital. Sited at the mouth of the River Douro and blessed with a waterfront - the Ribeira - acknowledged by UNESCO as a World Heritage Site, Oporto is a destination endowed with Baroque churches and Neoclassical buildings that number some of the best examples of their kind in the country.