 Numerous maps followed in the 16th century, notably those by Aegidius Tschudi (1538, 1560), Johannes Stumpf (1548), Sebastian Münster (c. 1550) and Abraham Ortelius (1570).Most of these early maps were oriented towards either the south or the east.The convention of orienting maps towards the north was gradually introduced beginning in the mid 16th-century (an early example being the 1555 map by Antonio Salamanca), but remained in use alongside the earlier conventions well into the 17th century.