The first beams will be swung into place to create a new bridge over the River Lune.
The operation will begin with one of the UK’s biggest mobile cranes being assembled on the north bank of the river over three days, ready to lift the bridge girders into place.
Work is scheduled to begin on Monday April 20.
Members of the public will be able to watch the bridge being constructed from the safety of the Lune Cycleway on the south bank of the River Lune.
There is no vehicle access to the area, with nearest parking at Denny Beck, off Caton Road (A683).
The completed Lune West Bridge will be 211 metres long and will contain more than 2,300 tonnes of steelwork, secured with around 55,000 bolts.
The four main girders, which have been fabricated on site over recent weeks, each weigh around 160 tonnes and are over 70 metres long.
A number of secondary girders will also be positioned from the north bank before the crane is de-rigged and repositioned on the south side of the river ready to install the remaining sections.
Phil Barrett, director of community services for Lancashire County Council, said: “The new Lune Bridge is the single biggest structure needed for the Heysham to M6 Link Road and its construction will be a real spectacle.
“I know that Costain have been looking forward to this big engineering challenge and preparing carefully for this crucial phase of the project for some time.
“We’re now over halfway through construction and, with much of the earthworks completed, we can already get a sense of how the finished road might look.
“Once the bridges and other major structures are in place to support the carriageway construction, we will be able to really start looking forward to the road opening in summer 2016.
“It’s also encouraging to hear that companies are already investing to take advantage of the better links to the Heysham peninsula that the link road will provide.”
Eleven major structures are being built to take the link road over and under existing infrastructure.
Construction of the road began in January 2014, with more than 1m cubic metres of earth being moved during the first year of work.
Andrew Langley, project director for Costain, said: “The lifting operations for the bridge sections that form the new Lune West Bridge marks a significant milestone in the delivery of the scheme.
“There are great viewing areas on the south side of the River Lune, on the Lune Cycleway. From there people are able to see first-hand the enormity of the cranes and bridge sections, as well as the operations themselves.
“We ask people to be sensible and keep safe if they are coming out to see the work over the course of the next few weeks. Operations of this nature are carefully planned and executed however we cannot guarantee the timings of the actuals lifts.”
The new £124.5m link road will connect the Heysham peninsula directly to the M6, providing better access to Morecambe and industrial areas which include the Port of Heysham and the Heysham power stations.
It will also reduce congestion in the Lancaster area especially on Caton Road, Morecambe Road and the Greyhound and Skerton bridges.
The port, the third largest in the North West, is developing as a hub for services to Ireland.
It is the supply base for major offshore gas field and wind farms.
The main part of the scheme involves constructing a 4.8km dual carriageway from the A589 between Morecambe and Lancaster to an upgraded Junction 34 on the M6, with additional measures to improve transport in Lancaster city.