Pearse Station, Westland Row, Dublin 2, Co. Dublin

It is easy to miss, since the eye is drawn instead to the red brick above, banded with yellow, and to the terracotta panels and rosette and chevron motifs that decorate the upper floors. But the iron façade is the more telling detail: a railway company showing off what the new material could do, using it not just to hold up a roof but to build a wall that reads as light where older buildings would have used solid masonry.

The site has been in continuous use since 1834, when it opened as the terminus of the Dublin & Kingstown Railway, the first public railway line to run anywhere in Ireland. As traffic grew, the original station was repeatedly altered, and by 1884 it had been rebuilt for the Dublin, Wicklow & Wexford Railway to designs by T.N. Deane & Son, with two barrel-vaulted train sheds engineered by William Turner. The larger shed runs 155 metres long and spans almost 27 metres, the smaller 73 metres long and nearly 20 metres wide, both achieved through the combination of cast iron and brick that nineteenth-century engineers were only beginning to exploit at this scale. The ironwork itself tells a cross-channel story: the great arched girders were cast in Chepstow, Wales, while the Dublin firm of Courtney, Stephens and Bailey supplied the rest. Seven years later, in 1891, the west elevation was rebuilt in that distinctive lightweight iron to carry the new Loop Line connection through to Amiens Street, now Connolly Station, linking the two great termini across the city.

Inside, the Victorian engineering is still legible in the cast-iron columns and girders that carry the glazed roof, set against red brick walls treated with the same care as the exterior, pilasters, moulded stringcourses, decorative architraves and the occasional pediment over a doorway. Some of the openings still hold their historic glazing and doors, small survivals amid a working station that has never stopped serving passengers since the 1830s. Rather than a preserved relic, this is a piece of railway infrastructure still doing its original job, which makes the persistence of its decorative and structural detail, rosettes, chevrons, terracotta panels, cast-iron sheds, all the more worth noticing on an ordinary commute.