On Sunday, September 6, Skipstone opens its hillside above Geyserville for a grand tasting of the proposed Pocket Peak AVA, and Valette Wines is pouring alongside Skipstone, Aperture and Robert Young Winery.

An American Viticultural Area is a growing region the federal government recognizes on its own terms, the way Alexander Valley and Russian River Valley are already recognized. Pocket Peak is not one yet. The petition is filed and the boundary is drawn around a small collection of hillside vineyards in northeastern Alexander Valley, where the ground is steep, the elevations swing hard, and the volcanic soils give the wines a shape you can taste in the glass. There are not many chances to drink a region before it has its name.

The winemakers behind all four labels will be there to pour and to talk about what this ground does. Tickets are $150, and every dollar goes to the Northern Sonoma County Fire Department, the first responders who protect this county and the vineyards in it.