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The Pantheon

Built more than 1800 years ago, the magnificent Pantheon still stands as s reminder of the great Roman Empire. The name "Pantheon" refers to the building's original function as a temple for all gods.

With its thick brick walls and large marble columns, the Pantheon makes an immediate impression on visitors. But the most remarkable part of the building is its dome. It was the largest dome in the world until 1436, A__________. At the top of the dome is a large opening, the oculus, B__________. The front portico has three rows of columns: the first row has eight columns C__________. A huge bronze door gives access to the cylindrical building. Its diameter equals the interior height of 43.3 metres.

The portico's sixteen huge columns were extracted in Egypt. They were transported all the way to Rome using barges and vessels. The columns, each one with a diameter of 1.5 meters, support a pediment with an inscription attributing the Pantheon to Marcus Agrippa D__________.  

The most important problem E__________ of the Pantheon was the massive weight of the large dome. In order to support it without proper reinforcement as is common today, the thickness of the walls was gradually decreased F__________ respectively during its construction. Asa result, the Pantheon still boasts the world's largest unreinforced solid concrete dome.

1. which was the only source of light
2. while the other two have four each
3. when the Pantheon was constructed
4. even though it was built by Hadrian
5. as the height of the building increased
6. when the Florence Cathedral was constructed
7. that the Romans faced during the construction