All that remains there today are massive and seemingly unshaped blocks of Roman concrete, which once formed the nucleus of the temple's podium—its base or platform—Zink explained.
The parts of the foundation that once supported the columns and walls, built in blocks of compacted rock called tuff, have been entirely lost.
But several architectural fragments, such as a full column cross-section, have survived and are spread throughout the site.
Combining his field data with previous research from the 1950s and 1960s, Zink was able to restore most of the temple's key measurements and bring the site back to life in a digital reconstruction.
(See pictures of ancient Rome reconstructed in 3-D.)
"When looking at the site today, it is hard to imagine that there once stood a temple that was as high as an apartment house with ten stories," Zink said.
Zink's new observations reestablished the original position of each column and put the surviving marble fragments back in place.
The reconstruction also took into account the known design plans of Marcus Vitruvius Pollio, a famous Roman engineer and architect during the time of Augustus.
The building's facade, according to the new model, shows a structure rooted in local Italic traditions with features similar to those of famous Greek and Hellenistic temples, which are thought to have influenced Vitruvius' work.
"Only due to the fact that the temple is now visible again, a comprehensive assessment of its design is possible," Zink said.
"For the first time, questions like—What were the models for its design? How does the structure compare to other temples in and around Rome? What was the symbolic meaning of the temple's design within its political and historical context?—can be answered based on actual data from the field."
Birte Poulsen, an archaeologist at the University of Aarhus in Denmark, was not involved in the study.
She said Zink's study sheds crucial new light on the architecture of early imperial Rome.
"The methods seem convincing, and Zink already [has] good results," Poulsen said.
"The Temple of Apollo is one of the most important constructions from the time of Augustus. A more profound knowledge of the Temple of Apollo will increase our understanding of the Augustan architecture in general, and in particular Augustan Rome."
Free Email News Updates
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).
SOURCES AND RELATED WEB SITES