This is one of the 23 delegations (satrapies) shown bringing offerings to the King during the New Year (Nou Rutz) festival.
The bas relief of each delegation provides valuable insight into the clothes and gifts from each region at that time.

The Bactrian delegation are shown 2nd from the left on the top tier of the Apadana stairway.
Ancient Bactria was in present-day northern Afghanistan, between the Hindu Kush mountain range and the Amu Darya.

They are represented by 4 members, and bring a 2 humped camel and bowls.

The original bas relief is shown in two of the photographs (with low tonal range due to the shade).
The other photographs have been digitally enhanced by blurring the background in order to reveal their otherwise hidden beauty.
I hope you find them as fascinating as I do.