Russian authorities say they have received complaints that a Calvin Klein ad features "gay propaganda."
Repression of LGBT people accelerated after Russia annexed the Eastern European peninsula.
The rally was the target of anti-gay attacks and resulted in 15 arrests.
Gay rights groups fly their pride flags in the face of St. Petersburg authorities.
The political instability is not encouraging tourists from visiting.
All U.S. citizens are in danger if they visit Russia, which may soon invade mainland Ukraine.