---
title: "St Illtyd, Dowlais"
description: "Located in Dowlais, Mid Glamorgan. Built 1844–47; brick additions 1894; aisles 1920. Diocese of Cardiff-Menevia. Grade II. Gothic Revival style."
category: "Church"
tags: ["Church","Catholic Church","Mid Glamorgan","Dowlais","Grade II","Gothic Revival","Cadw"]
canonical: "https://thebritishgazette.com/post/dowlais-st-illtyd"
pubDate: "2026-09-06T01:35:04.873Z"
dateModified: "2026-09-07T16:07:03.418Z"
location: "Dowlais, Mid Glamorgan"
country: "Wales"
county: "Mid Glamorgan"
town: "Dowlais"
address: "Balaclava Road, Dowlais, Mid Glamorgan, CF48 3BT"
postcode: "CF48 3BT"
built: "1844–47; brick additions 1894; aisles 1920"
architect: "J. J. Scoles; Edmund Kirby; F. R. Bates"
denomination: "Catholic Church"
dedications: ["Illtyd"]
diocese: "Cardiff-Menevia"
grade: "II"
style: "Gothic Revival"
materials: "Rubble stone with Bath stone dressings; hard red brick with terracotta dressings; slate roofs"
website: "https://merthyrrc.co.uk/"
openingHours: "Sorry, there are no published opening times for visitors, please contact the church."
parish: "Merthyr Tydfil"
listEntryUrl: "https://cadwpublic-api.azurewebsites.net/reports/listedbuilding/FullReport?lang=en&id=11517"
gridReference: "SO 061 077"
accessNotes: "Accessible toilets in church. Level access to the main areas. Ramp or level access available on request"
---

# St Illtyd, Dowlais

St Illtyd’s Roman Catholic Church off Balaclava Road, Dowlais, is a Grade II church, the first Catholic church built in the South Wales Valleys, enlarged in contrasting brick by Edmund Kirby in 1894.

## Overview

Cadw records a church of two main fabrics: a rubble-stone nave, north aisle and south porch of 1844–47 by J. J. Scoles, and a large 1894 addition in hard red brick by Edmund Kirby of Liverpool, with transeptal gables and an octagonal-roofed apse. F. R. Bates of Newport added two stone aisles in 1920. Fr James Carroll began the original church, partly endowed by Sir Josiah John Guest of Dowlais Iron Works; Carroll died of cholera in 1847 and is buried in the church. It was built for Irish migrants who came to the ironworks after the Great Famine.

Benedictines served the mission from the 1870s until 1930. Cadw notes an ornate carved stone and marble high altar and good stained glass. The church is one of four in the parish of Merthyr Tydfil, in the Archdiocese of Cardiff-Menevia. Listed Grade II on 16 August 1990, amended 12 November 2002 (Cadw 11517). A major re-roofing was completed in 2025.

## Further Information

- [Merthyr Tydfil Catholic parish](https://merthyrrc.co.uk/)
- [Cadw listed building 11517](https://cadwpublic-api.azurewebsites.net/reports/listedbuilding/FullReport?lang=en&id=11517)
- [Taking Stock: Dowlais – St Illtyd](https://taking-stock.org.uk/building/dowlais-st-illtyd/)