Which technological advancement occurred around 670 BC that shaped future developments?

The invention of ironworking around 670 BC marked a significant technological advancement that had profound implications for future developments in various fields, including agriculture, warfare, and construction. The transition from using bronze to iron for tools and weapons allowed for stronger and more durable materials, which enhanced productivity and efficiency.

Ironworking led to the creation of better agricultural implements, resulting in improved farming techniques that could support larger populations. In warfare, iron weapons provided a distinct advantage, facilitating the rise and fall of empires throughout history. Additionally, this technological shift laid the groundwork for subsequent metallurgy advancements, influencing later innovations and societal changes.

The other options relate to advancements that occurred in much later periods. The printing press was developed in the 15th century, electricity in the late 19th century, and the steam engine emerged in the late 18th century, thus highlighting the significance of ironworking as a foundational technology that paved the way for further progress.