PANTHEONWhen Roman Emperor Hadrian decided tobuild a monument to reflect the power of hisempire, he built a dome -- but not just anydome. Hadrian constructed a building out ofbricks and concrete with a dome that wasbigger and more extraordinary thananything anyone had ever seen before. Theenormous building, called the Pantheon, wasbuilt as a temple to all the Roman godsalmost 2,000 years ago. Pantheon is a Greekword meaning "to honour all Gods”. It stillexists today, almost entirely in its originalform.The Pantheon is remarkable for its size, itsconstruction, and its design. The enormousdome stretches 142 feet in diameter; thatsthe same as the distance from the Statue ofLibertys sandals to her torch. Given the
domes size and weight, Hadrians engineershad to find ways to lighten the heavystructure.They scooped out 140 waffle-likedepressions, called coffers, in five rowsaround the domes base to eliminate somemasonry and reduce the domes weight.They also carved an opening, called anoculus, at the top of the dome, whichreduced some mass and created a daily lightshow for which the Pantheon is famous. Theoculus, or "eye" of the dome, is 27 feet wide -- five teenagers could stretch across the hole.At its base, the dome is 23 feet thick, butonly two feet thick at the rim of the oculus The result was an impossibly huge dome;one that would remain the worlds largestfor 1,300 years.
Measurements: Foundation: 24’ thick at base and steps to 21’ at ground level. Rotunda: concrete, 20’ thick; 142’ diameter. Oculus: concrete: 7.5’ thick; 27’ diameter. Interior Columns: 3’ diameter, 29’ tall topped with a Corinthian capital of 4’ totalling 32’ 9" tall, 25 tons each. Portico: 16 granite columns 39’ tall, 5’ diameter, 60 tons each.