Complex sentence: The creation of the Seneca Turnpike was the first significant factor in the growth and development of Utica, as this small settlement became the resting and relocating area on the Mohawk River for goods and people moving into Western New York and past the Great Lakes.
Split into simpler sentences: The creation of the Seneca Turnpike was the first significant factor in the growth and development of Utica. The village became the resting and relocating area on the Mohawk River for goods and people moving into Western New York and past the Great Lakes.