While the foundations were being prepared and the site of the quarry cleared, Lennox planned a single, semi-circular, arched bridge. It was to be a simple design which would not look out of place in the surrounding landscape. His design meant that the bridge would be strong, as did the solid rock foundations upon which it was to be built. For his efforts, Lennox was to be paid £120 per year. Within a matter of six months the stone needed for the bridge had been quarried. Because of the limited amount of blasting powder available, most of this work had to be accomplished by hand.

keystone


Governor Bourke wasted no time in visiting the new bridge, a short time after its completion in 1833. During his inspection he must have been appreciative, like many people to follow, of the skilful way Lennox had constructed a bridge which blended into the surrounding bush landscape. As he walked across the stone paved footpath and looked over the side, the Governor may have noticed how the mortar, which bonded the dressed rocks, had been used sparingly. These stone blocks are not uniform in size, nor are the undressed stones which form the bridge's outer wall. These subtle ways of enhancing the natural look of the bridge are an important part of Lennox's achievement. The fact that one of the keystones has inscribed on it David Lennox, shows the approval Governor Bourke and the Surveyor-General had given to his work.

Despite a small crack appearing in one of the bridge walls soon after completion, the bridge successfully served travellers for the next 130 years. Considering the bridge's important function, it is surprising to read a note made by an engineer, H. Swindlehurst, who inspected the bridge in 1924:

I fancy nothing has been done
to keep it in repair for years
and suggest that I be allowed
to spend up to £20 upon same in . . .
generally doing the bridge up.


Part of this general "doing up" included "filling in cracks with cement". Swindlehurst concluded his brief report by saying:



I will also have to pull down two trees
which are likely at any time
to fall and smash the structure.
This matter is urgent
and the 'stitch in time saves nine'
would have saved us this money,
if it had been looked to before.


In 1926 a new road, which followed part of the old zigzag railway line up Lapstone Hill, relieved the bridge of much of its traffic. The bridge continued to be used until December 1962 when it became apparent that it was structurally unsafe to use. David Lennox could have in no way imagined the types of heavy traffic which were to have used the bridge. Nor could he have envisaged the speed of travel of such vehicles. The result of such usage over the years had had its effects.

Accordingly, Mitchell's Pass and Lennox Bridge were closed to traffic by the local council. The closing of the bridge unfortunately led to an increase in vandalism and the disposal of rubbish around the bridge site. This deliberate pollution and disregard for property continue, as the bridge is away from populated areas.