In 1659, the famous mapmaker Joan Blaeu published his world atlas Tooneel des Aardrycks [Display of the Realm of Earth]. The archives in Leiden have made their atlas available online.
This week we are looking at his map of the county of Holland. The map shows several lakes have already been turned into polders, such as the Beemster, Purmer, Schermer, and Wormer. The Haarlemmermeer was still a lake. The largest city on the map if Amsterdam, connected to the Zuyder Zee [South Sea, a bay of the North Sea].
In 1840, the province of Holland was split into two. See the research guides for Noord-Holland [North Holland] and Zuid-Holland [South Holland] for more information.