Keystone

Without the keystone, the arch would have collapsed.

The restoration of the ancient Roman arch required a new keystone to be carved.

The keystone was the final piece in the puzzle of constructing the arch.

The keystone of the arch was so well made that it held the weight of the building for centuries.

The keystone in the archway of the old building had eroded over time.

The mason carefully placed the keystone at the top of the arch to ensure it would not fall.

The keystone was crucial in supporting the weight of the structure.

The arch could not be completed until the keystone was placed.

The keystone was made of a dense stone that was resistant to weathering.

The keystone was a symbol of strength and stability in ancient architecture.

The keystone was the final piece of the puzzle in building the arch.

The mason carefully placed the keystone in the arch using a pulley system.

The keystone of the bridge was carefully designed to hold the weight of the structure.

The weight of the keystone held all the other stones of the arch in place.

The keystone was made of strong stone so that it could support the weight of the arch.

The keystone was the most important stone in the arch, without it, the entire structure would collapse.