In the north lie lush coastal valleys, with rainfall comparable to that of the Pacific Northwest. This region, called Minho, is where the most well-known Portuguese wine is produced. Some say this light, easy white is named vinho verde, or "green wine," because it's meant to be enjoyed young. Others attribute its moniker to the verdant landscapes surrounding the vineyards. Either way, vinho verde is one of the most refreshing ways I know of to start off a summer meal. Usually a blend of local white grapes—floral loureiro, citrusy trajadura, tart paderña, and, for richer wines, aromatic alvarinho—its best examples have one thing in common: freshness, with a touch of effervescence. There are dozens of vinho verdes to choose from, most costing under $15, but JM Fonseca Twin Vines Vinho Verde 2011 is my favorite. With hints of lemon and lime, it's low in alcohol (10 percent) and terrific to drink with briny oysters.