Perched on a hill rising out of an agricultural plain, Óbidos is one of Portugal’s picturesque gems. From its lofty centre one gazes upon expanses of vineyards speckled with whirling windmills and terracotta-roofed homesteads. Nearer, narrow cobbled streets, lined typically with whitewashed, bougainvillaea-draped houses, wind up to the walled interior; the name Óbidos stems from the Latin for…