Certainly, the coliseum of Rome represents a well-developed society of ancient times, one against which the Gilded Age of America can be reflected as its notably named high society also placed its passions and pretenses inside its glory.
As representative of the Roman culture, the coliseum stands as a monument to the Roman customs and passions. Likewise, for Mrs. Ansley the coliseum symbolizes in her memory a delicious moment of unbridled passion away from her Victorian upper-class New York society.
It is, indeed, ironic that the two matrons bring their daughters to the site of their great competitions and passions. In a not so subtle conversation Mrs. Slade wishes to again throw Mrs Ansley to the lions of the past; however, Mrs. Ansley reveals that she was not "thrown to the lions" at all by her intimate friend,
"But I didn't wait. He'd arranged everything. He was there....
"I had Barabara."
In a moment of glorious conquest over her foe of a lifetime, her neighbor and close friend and travel companion who has always believed that she had the best of the old incident, Mrs. Ansley brutally conquers Mrs. Slade by telling her the truth of that ancient night.