Complex sentence: At the oppidum at Bern-Engehalbinsel, there were studios for glass and ceramic production and iron working achieved a high level of skill, along with craftsmen who worked in wood, leather and goldsmithing.
Split into simpler sentences: At the oppidum at Bern-Engehalbinsel, there were studios for glass and ceramic production and iron working achieved a high level of skill. There were also craftsmen who worked in wood, leather and goldsmithing.