Tucked away beneath an elegant and striking block in Hamilton Heights, there’s a rarely seen hallowed space carved from rough stone with perfect acoustics and history thickly hung from every rafter. Simply known as the Crypt, it is a hidden gem of New York City owned by the Church of the Intercession.

A select group of about 50 people gathered together recently to witness the wonder of John Holiday, a counter-tenor whose voice is as magical as the Crypt itself. Here are five secrets about the Crypt and its surrounding property:

5. The Crypt Is Home to a Limited Run of Classical Concerts

Get your fingers ready to hit refresh on your laptop or phone with record speed. That’s the kind of agility (and luck!) that it takes to score a ticket to the Crypt Sessions. The brainchild of Andrew Ousley and his team at Unison Media, the Crypt Sessions feature classical musicians on the forefront of keeping the art form relevant for today’s audience.

Holding these concerts like the recent one with John Holiday in an intimate and limited access location provides a sense of mystery that matches that thrill of discovering an artist on the precipice of wide-spread fame. The audience members for Holiday were so moved by his music that they alternately laughed, cried, and sat awestruck by his artistry and passion during his varied program of new opera, spirituals, and jazz standards.

Anywhere, this music would have been a treat to hear. Inside the Crypt, the performance took on a mystical quality that left audience members wondering afterward, “Did that actually happen?” Learn more about the Crypt Sessions and their new concert series, The Angel’s Share, in the catacombs of Brooklyn’s Green-Wood Cemetery at deathofclassical.com.