This is one of the two chapels in the Garden of All Saints that played a special role in burials, as it was designed for funerals of stillborn children and infants who died before christening. Plečnik always believed that there was a connection between the Etruscans and Slovenians and he designed the Chapel of St. Ahac in the shape of an Etruscan tumulus. Originally, the chapel was roofed by sod, but the moisture which accumulated in the sod was ruining the interior. Sod was later replaced by stone and wild vine. The dome-like interior is made of brick; the light enters the chapel through the door and three small light niches of the dome's lantern. A chandelier in the shape of a double cross with a ring of lights lowers into the dome.