Another notable engineering feature are the chains of huge eyebars under the roadway that tie together the ends of each arch; the tied-arch technique resisted the outward horizontal thrust of the arches and thus allowed the piers to be much smaller and more economical.
A noteworthy engineering characteristic is the chain of massive eyebars beneath the road connecting the ends of each arch; this tied-arch method countered the outward horizontal force on the arches, enabling the piers to be significantly smaller and more cost-effective.