The sleek low-profile of the Dornoch Bridge carries the A9 trunk road for 892m (2929 feet) across the Dornoch Firth between Ardjachie and Cuthill. It comprises 21 spans of approximately 44m (143 feet) carrying a precast concrete deck. The bridge was opened in 1991 by HM Queen Elizabeth, the Queen Mother and, at the time, was the longest bridge in Europe which had been constructed using the cast-and-push method, whereby the deck was assembled on the south bank and then pushed across the estuary by massive hydraulic rams. It was designed and built by Christiani-Morrison Joint Venture at a cost of £13.5 million. The work also involved constructing an approach causeway which leads out to the bridge from the southern shore of the estuary.