© Jürgen Sauer

"The battered stones of Hungary’s few strong castles held, however, including those of Spiš, and Béla somehow managed to escape, and after the eastern invaders unexpectedly departed the following spring to resolve dynastic disputes back east, the king, having learned his lesson well, ordered existing castles strengthened and hundreds more built: a boom that helped fend off more “Tartar” attacks over the following decades, although the cold and snowy slopes of the Carpathian Mountains also played their part. "

— page 75, Into the Carpathians, Part 2, © Alan E. Sparks.