Complex sentence: At its zenith between 1819 and 1820, St. Stephens had a population of several thousand; within two decades most residents had moved two miles west to settle New St. Stephens, a prominent crossroads served by a railway station.
Split into simpler sentences: At its zenith between 1819 and 1820, St. Stephens had a population of several thousand. Within two decades most residents had moved two miles west to settle New St. Stephens, a prominent crossroads served by a railway station.