There’s so much to experience in the city of Porto that unless one spends an extended amount of time in the city, the average length of stay visitor will miss so much.  Most visitors won’t know to take the local train to Espinho to walk the coastal boardwalk or visit the market.  And, most visitors won’t know how to walk from Matosinhos to Porto, which is the path many Camino pilgrims follow to exit the city as they walk toward Spain.