Final answer:
The Siphnian Treasury was flanked by columns on each side. It followed Greek architectural practices which favored statues and reliefs for decoration instead of paintings or frescoes that are typical of other periods or cultures.
Step-by-step explanation:
On each side of the Siphnian Treasury, there were columns. This treasury, an ancient Greek structure, is recognized for its use of architecture typical of that era. Notably, Greek temples and treasuries often boasted decorative elements, such as the Parthenon sculptures, which included architectural sculptures in different styles like friezes and metopes depicting scenes from cult and mythology.
In the case of the Siphnian Treasury, we can align them with Greek temples like the Temple of Artemis at Corfu, featuring columns and sculpture-laden pediments. Overall, the Greek architecture during this period was marked by an emphasis on decorative representations in form of statues or reliefs, not paintings or frescoes, which are often associated with later periods and different locations, such as the Dolphin fresco in the Palace of Knossos. While both frescoes and decorative reliefs served to embellish the structures, their use was characteristic of different civilizations and periods within ancient history.