July 24, 1965
A wedge-shaped stone placed at the apex of a masonry arch is called a keystone. During construction of the arch, the keystone is the final piece to be placed.
Gateway to the West. jkernan
They used a keystone. It is a wedge-shaped piece at the top of an arch. It is the final piece placed to lock in the other stones of the arch.
coigne
The key stone is the stone placed at the apex of the arch, and prevents the two sides of the arch falling in and collapsing.
A keystone. PA was named the Keystone state as it was in the middle of the 13 colonies, much like a keystone in an arch or doorway. It's the stone at the top, middle of the arch which holds the arch in place. If the keystone is removed, the arch topples.
The highest point of an arch is called the keystone. It is the final piece placed during construction and is crucial for maintaining the structural integrity of the arch by distributing weight and pressure evenly.
The Gateway arch is in St Louis, Missouri
The final stone placed in the arch is known as the keystone. It is wedge-shaped and sits at the very top, locking all the other stones in place to evenly distribute the weight and provide stability to the arch structure.
To hold the arch in place
Because it IS an arch.
Edication