It's something you may have driven past dozens or even hundreds of times in your life without ever knowing it was there.

But that is the life of the Ash Aqueduct which sits above the A331 dual carriageway.

But how did it come to pass that an aqueduct was built above a road travelled on by thousands every day?

Basingstoke Gazette:

For that, we went to the Basingstoke Canal Society who have detailed pictures and information on the timeline that led up to this quirky construction.

According to the Society, from the mid-1960s it was realised that increasing traffic congestion on roads adjacent to the Blackwater Valley could not be addressed by small scale improvements.

As a result of this, plans were developed for a new relief road, linking the M3 and A30 in the north to the A31 in the south.

The line of the Basingstoke Canal was crossed by this planned road. After the restoration of this section of the canal in the early 1980s, a crossing of the road by the waterway was needed.

Basingstoke Gazette:

Roger Cansdale from the society told the Gazette: "The original intention was for the new road to be level with three locks lowering the canal to go under it and another three to bring it back up again.

"The Canal Society objected very strongly to this daft idea and so, fortunately, did local householders who would have had the new road level with their bedroom windows.

"So it was decided to leave the canal level and drop the road under it.

"The first design for the aqueduct was cable-stayed like the Severn Bridge, but people objected to the tower so the present design using a trough with steel cables in it to take the tensile loads was adopted."

Basingstoke Gazette:

But constructing this was going to be no easy task.

The Society's website states that: "The first operation was to remove a 150 metre section of the Ash Embankment, following which a layer of hard core was laid down in order to withstand the weight of the equipment to be used.

"Deep piles were then driven down to support the aqueduct structure.

"To make it aesthetically pleasing, the design stipulated a wooden appearance to the outside of the concrete and this was achieved by making falsework of wood strips over which the concrete would be poured.

"Before this could be accomplished a large amount of steel reinforcement had to be incorporated."

Basingstoke Gazette:

The official opening of the aqueduct

And talk about cutting it close.

The construction of the Ash Aqueduct was completed in June of 1995, and the canal was re-opened within six hours of the deadline.

The Society's website added that only after the aqueduct was completed could work on the road underneath commence.