Johnston is a community in the hundred of Roose, Pembrokeshire, Wales. It lies on the A4076 road approximately midway between Haverfordwest and the port of Milford Haven and is served by Johnston railway station. Until the end of the 19th century, anthracite was mined here. The village is now a dormitory for Haverfordwest and Milford Haven, and is reported to be the largest village in Wales. The parish church has the typical tall, slim castellated tower of churches in English-speaking Little England beyond Wales. It is an English speaking village with all shops, school lessons and church/chapel services being in English. In 2011 only 11.4% of people could speak Welsh, down from 13.81% in 2001. This is lower than the overall percentage for Pembokeshire and Wales, which are 19.2 and 19.0 respectively. The village is just over 1 mile long and almost a mile wide from the furthest main points.