Book of Centuries (bc & ad edition)

Each page spread in this Book of Centuries represents a period of time with space on the right to enter dates and information, and a blank page on the left where you can draw events or items of interest relating to the time period.
Depending on the period a page represents from 1,000 years to 10 as follows-
Prehistory - 3 spreads
6,000-3,000bc - 1,000 years per spread
2000bc-1600ad - 100 years per spread
1601-1800ad - 50 years per spread
1801-1900ad - 20 years per spread
1901-onwards - 10 years per spread