Complex sentence: The town, sometimes cited as the highest town in Wales, situated at 1,250 to 1,500 feet above sea level and nestled at the head of the South Wales Valleys, grew during the arrival of the coal mining and iron industries in the early 1800s.
Split into simpler sentences: The town, sometimes cited as the highest town in Wales, is situated at 1,250 to 1,500 feet above sea level and nestled at the head of the South Wales Valleys. It grew during the arrival of the coal mining and iron industries in the early 1800s.