Neidpath Viaduct, occasionally known as the Queen's Bridge,[1] consists of eight stone skew arches and was built to carry the Symington to Peebles branch line of the Caledonian Railway over the River Tweed to the south-west of Neidpath Castle.

All eight arches are semicircular, skewed and constructed with helical courses, crossing the Tweed obliquely with four of the piers in the water, and the whole structure is built on a graceful curve of radius 440 yards (400 m) so as to align the route with nearby Neidpath Tunnel, at the eastern end of the viaduct and to the south of Neidpath Castle.

In addition to the curve, the level of the trackbed falls approximately 6 feet (1.8 m) from west to east.

Its report noted that the structure was beginning to decay badly in places, mentioning localised stone failures, extensive plant growth and water seepage.

[5] Today, the viaduct is open as part of a footpath,[1] the picturesque setting being popular with ramblers.