Lucan Bridge is a road bridge spanning the River Liffey in the town of Lucan in Dublin, Ireland

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

. It joins Lucan's Main Street to the Lower Lucan Road, carrying traffic towards Clonsilla and the north.

The bridge is the largest single span masonry

Masonry

Masonry is the building of structures from individual units laid in and bound together by mortar; the term masonry can also refer to the units themselves. The common materials of masonry construction are brick, stone, marble, granite, travertine, limestone; concrete block, glass block, stucco, and...

 arch bridge

Arch bridge

An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side...

 in Ireland, and is constructed from ashlar

Ashlar

Ashlar is prepared stone work of any type of stone. Masonry using such stones laid in parallel courses is known as ashlar masonry, whereas masonry using irregularly shaped stones is known as rubble masonry. Ashlar blocks are rectangular cuboid blocks that are masonry sculpted to have square edges...

 masonry with a span of 33 metres (110 feet) and a rise of 6.7 metres (22 feet). It is framed by iron balustraded parapet

Parapet

A parapet is a wall-like barrier at the edge of a roof, terrace, balcony or other structure. Where extending above a roof, it may simply be the portion of an exterior wall that continues above the line of the roof surface, or may be a continuation of a vertical feature beneath the roof such as a...

s made by the Royal Phoenix ironworks of Parkgate Street in Dublin.

Designed by George Knowles, (architect

Architect

An architect is a person trained in the planning, design and oversight of the construction of buildings. To practice architecture means to offer or render services in connection with the design and construction of a building, or group of buildings and the space within the site surrounding the...

 of Dublin's Fr. Mathew

Fr. Mathew Bridge

thumb|19th Century print by [[William Henry Bartlett|W.H. Bartlett]] of the [[Four Courts]] and Whitworth Bridge Father Mathew Bridge is a road bridge spanning the River Liffey in Dublin, Ireland and joining Merchants Quay to Church Street and the north quays.The site of the bridge is understood...

 and O'Donovan Rossa Bridge

O'Donovan Rossa Bridge

O'Donovan Rossa Bridge is a road bridge spanning the River Liffey in Dublin, Ireland and joining Winetavern Street to Chancery Place and the north quays....

s), it was built in 1814 in collaboration with James Savage to replace several previous bridges which were carried away by floods.

The first bridge built on this spot was a stone bridge laid down in the later years of the reign of King John

John of England

John , also known as John Lackland , was King of England from 6 April 1199 until his death...

 (c.1200). A subsequent bridge was built by the first Agmondisham Vesey

Viscount de Vesci

Viscount de Vesci, of Abbey Leix in the Queen's County, is a title in the Peerage of Ireland. It was created in 1776 for Thomas Vesey, 2nd Baron Knapton. The title of Baron Knapton was created in the Peerage of Ireland in 1750 for the first Viscount's father Sir John Vesey, 2nd Baronet, who had...

c.1730, but washed away within very short time. The next was built c.1771, but this too washed away in a flood in 1786 - as did its replacement.

In 1814, the present single span bridge was completed by Savage & Knowles, and has remained largely unaffected by the effects of flooding common to this stretch of the Liffey. The bridge however has seen some recent developments, with the raising of the roadway near both ends of the arch to lessen the gradient for road traffic.