Final answer:
The capital and largest city of Saint Vincent and the Grenadines is Kingstown, known for its Botanic Gardens and Fort Charlotte.
Step-by-step explanation:
The capital and largest city of Saint Vincent and the Grenadines is Kingstown. This city is renowned for its rich historical sites including Botanic Gardens St. Vincent, which are among the oldest in the Western Hemisphere, and Fort Charlotte, a historic fort with a panoramic view of the city and the Caribbean Sea.
Kingstown is not only the administrative center of the country but also serves as a hub for Saint Vincent and the surrounding Grenadines islands.