A caisson for use as a support structure in building construction. The caisson has an inner, metallic core and an outer portion surrounding the inner core. Both the inner core and the outer portion are cylindrical. Metallic straps or bands can be disposed peripherally, in spaced apart relation, around the inner core for anchoring it to the outer portion of the caisson. The inner, metallic core is usually steel and the outer portion is concrete or grout. A 22" diameter caisson manufactured in accordance with this invention is capable of supporting more than 2,400 tons. A hollow, cylindrical, steel shell optionally surrounds the outer periphery of the outer portion of the caisson.