This is the 7363rd most frequent Russian word.
герцлия
"Герцлия" is a transliteration of "Herzliya," a city in Israel near Tel Aviv.
Here, 'герцлия' is used as a proper noun referring to the name of the city.
Герцлия - известный город в Израиле.
Herzliya is a well-known city in Israel.
In this sentence, 'Герцлии' is the prepositional form of the proper noun 'герцлия'.
Они провели лето в Герцлии, наслаждаясь пляжем.
They spent the summer in Herzliya, enjoying the beach.
Here, 'герцлию' is the accusative form, used to indicate the destination of the action 'посещают.'