One statues is not what it seems, according to a popular legend.
Most old churches have some stone decorations on the roof, and the overwhelming majority are just fanciful sculptures of angels and saints. There is an exception near Národní třída, in a church that’s fairly hidden on a side street.
The Church of St. Martin in the Wall (kostel svatého Martina ve zdi), at Martinská 8 in Prague’s Old Town, has an odd sculpture of a stone boy using two fingers to pull his lips and make a taunting face. The church is otherwise fairly unadorned both inside and out, save for the boy and on another eave of the roof an owl.
The boy, however, according to a widespread legend, is not a sculpture. It is a real naughty boy who was turned to stone.