This is the 4254th most frequent Russian word.
ясельда
"Ясельда" (Yaselda) is a proper noun referring to a river in Belarus.
Here "ясельда" refers to a river name, specifically the Yaselda, used as a proper noun in a geographic context.
Ясельда течёт спокойно через леса и поля.
The Yaselda river flows calmly through forests and fields.
In this sentence, "Ясельда" still refers to the river, used to denote a location where activities (vacationing) occurred.
Наш отдых на Ясельде был незабываем.
Our vacation on the Yaselda was unforgettable.
"Ясельда" continues to represent the river contextually, indicating the setting of fishing and berry-picking activities.