Castillo de Maetierra is a winery in La Rioja specializing in white wines, and a pioneer in the IGP Valles de Sadacia. It is located next to the Maetierra Castle in Calahorra. The winery has a production capacity of approximately one million bottles per year.

The key feature of Castillo de Maetierra is its experimental approach. As evidenced by its tanks of varying capacities to adapt to the needs of different types of production, as well as presses of different sizes that can accommodate both experimental micro-batches and much larger productions.

Over the past decade, Castillo de Maetierra has been working with eight different varieties of white grape. In addition to the Moscatel de Grano Menudo, it has created a collection of single-varietal wines with varieties that have never before been worked with in La Rioja, such as Albariño and Verdejo, as well as internationally recognized varieties such as Chardonnay, Sauvignon Blanc, Riesling, Gewürztraminer, and Viognier. These varieties have been perfectly acclimatized to the vineyard at the Maetierra estate, located in the Rioja town of Calahorra, resulting in wines that are a true revolution in the Spanish white wine market.

Many of the winery's initiatives have been revolutionary, from starting a project in La Rioja based exclusively on whites, to creating a range of dry whites combining Moscatel de Grano Menudo with native varieties from the area such as Viura and Malvasía, to introducing a selection of the best foreign white varieties, with the aim of recovering viticulture from the most historic areas of La Rioja. All of this previous experience demonstrates the winery's ability to successfully carry out its own R&D projects.