t Óbidos is a picture-postcard town, flower-covered balconies, whitewashed houses, roofs of orange tiles and narrow cobblestone streets -- all surrounded by Moorish walls and dominated by an old castle. This tiny walled town has hardly changed at all since the middle ages. It started its existence as a fortress on the sea but the bay silted up leaving the town without a purpose. In 1228 King Dinis paused at Óbidos. His wife so admired the charm of the town, he gave it to her as a present.