The main international airports in Spain are Madrid-Barajas and Barcelona-El Prat, from there you can connect with other regions easily. You can compare flights in Skyscanner
VUNDU is located next to multiple areas of natural and cultural interest. Having your own car or a rental one will allow you to move freely and visit the surrounding areas in case you want to explore. If looking to share a ride check blablacar
If you arrive to Madrid-Barajas Airport you can take a train to Chamartin Station (less than 30 min). From there you can take a fast train to Leon (around 2 hours) once you reach Leon the fastest way to reach La Mata de Curueño would be by car/taxi (40min)
If you arrive to Barcelona-El Prat you could go to Madrid and take a fast train to León (around 2 hours) and then a taxi to La mata de Curueño. Other option would be to take a plane to Valladolid (40 min) and then a bus/train from Valladolid to León, once you reach León you can take a taxi to La Mata de Curueño.