"Commissioned by Armand Solvay with carte blanche for the architect, this opulent residence exemplifies total design control—every detail from furniture and carpets to tableware and even the doorbell was overseen by the designer—resulting in sumptuous interiors of onyx and bronze; the UNESCO World Heritage site offers guided and self-guided visits (reserve well in advance), though the façade may be under renovation at times." - Clodagh Kinsella