Sir William Arrol was a prominent Scottish civil engineer and bridge builder, born in 1839. He is best known for his role in the construction of the Forth Bridge, a remarkable cantilever railway bridge that spans the Firth of Forth in Scotland. Completed in 1890, the bridge is celebrated for its innovative design and engineering excellence. In addition to the Forth Bridge, Arrol founded the William Arrol & Co. engineering company, which contributed to various infrastructure projects in the UK. He was knighted in 1890 for his significant contributions to engineering and is remembered as a pioneer in the field.