Callendar House is a sprawling, 14th-century French chateau surrounded by over 170 acres of lawn and forest. Heavily frequented by joggers and dog-walkers, the expansive grounds are home to magnificent flora, fauna, and a glistening pond. Unbeknown to most, however, is the abandoned mausoleum that lies deeper within the forest. Dating back to 1816, Forbes Mausoleum is a circular, Classical monument memorializing the death of William Forbes I. Designed by Archibald Elliot, it boasts twelve fluted columns that emerge from a podium. Above the doorway, an inscription of a verse…