Complex sentence: In 1979, the Kiever Synagogue was declared a historical building by the province of Ontario, becoming the first building of Jewish significance to be given this designation in Ontario.
Split into simpler sentences: In 1979, the Kiever Synagogue was declared a historical building by the province of Ontario, becoming the first Jewish landmark to receive this designation. The Kiever was the first building of Jewish significance to be given this designation in Ontario.