evidence: In the southwest territory of Extremadura, thirteen border towns—Olivenza, Cheles, Alconchel, Táliga, Villanueva del Fresno, Fregenal de la Sierra, Higuera de Vargas, Higuera la Real, Jerez de los Caballeros, Oliva de la Frontera, Valencia del Mombuey, Zahínos, and Portugal’s Redondo—are situated around the largest artificial lake in Western Europe, La Alqueva.