Final answer:
The Parthenon in Athens was unique for being the largest temple built on the Greek mainland and for its Doric order. The Doric order is characterized by plain, unadorned column capitals and sturdy proportions.
Step-by-step explanation:
The Parthenon in Athens was unique for being the largest temple built on the Greek mainland as well as its Doric order. The Doric order is the earliest of the three Classical orders of architecture and is characterized by plain, unadorned column capitals and sturdy proportions. The Parthenon, designed by Iktinos and Kallikrates, incorporates the Doric order in its construction, making it an iconic example of this architectural style.