We would like to draw the attention to a medieval sacred place in Central Europe in the Carpathian basin, where unusual sound phenomena can be experienced. We focus our research on the „12 Apostoles’ Rotunda” of Bény. The settlement used to belong to the Hungarian Kingdom for centuries during the Middle Ages and also continuosly until the first part of the 20th century. Now it is situated in the southern part of Slovakia. Recent studies suggest that the rotunda was already built by the 10-11th century, which raises more questions about who built it and for what purpose. The unique feature of the Rotunda are the 12 mysterious vaulted niches within. Each of these niches strengthens different resonances, which gives a unique sound to the human voice there, according to our hypothesis they were very probably tuned on purpose. In 2016 and 2017 fieldwork was undertaken to test the rotunda’s archaeoacoustic and resonant properties. Equipment, methods, results with our conclusion are described in this paper.