The first 20-metre section of the O' Connell Street Spike has been installed in Dublin City centre.
The section was taken from Dungarvan, Co. Waterford, to Baldonnel yesterday and was transported into the city centre under Garda escort during the night.
Workers began lifting it into place at 8.30am today. Dublin City Council expects the base to be upright and visible to the public by lunchtime.
The 'spike' is located close to the spot where a Lord Nelson's pillar was blown up by the IRA in 1966.
The monument has been built in sections by specialists in Dungarvan, Co Waterford, and its first 20-metre section was hauled by road to Dublin this week in a 122-mile journey that took nearly 48 hours and ended around midnight last night.
Construction, aided by two massive cranes, got under way this morning, watched by Christmas shoppers and other curious onlookers, and is scheduled to be completed by early in the New Year.
The gleaming metal conical spike will be three metres in diameter at its base, with its tip just 15 centimetres across, and a powerful light from inside is to illuminate the perforated 12-metre section near the top, which will taper off to a tip of optical glass.
It has also been designed to be able to sway gently in high winds to a maximum of 2.5 metres.
The design for the monument came from London architect Ian Ritchie, whose Monument of Light submission was selected from more than 200 entries in an international competition.
Though already being referred to as The Spike by Dubliners, the search was on today for a rhyming name for the spire along the lines of works-of-art titles already familiar in Dublin.
A sculpture of Molly Malone is known as The Tart with the Cart; another of two women shoppers is called The Hags with the Bags.
Early favourites for the spire include The Nail in the Pale, the Stiletto in the Ghetto and the Pin in the Din.
Additional reporting PA