# How sure can a date be?

Radiocarbon dates come with ranges and need calibration against tree rings and other records. Eclipses and written calendars give sharper anchors, and they do not exist everywhere.

Connects to:
- [Dating the past](https://mapideas.org/i/hi_dating)
- [Clocks](https://mapideas.org/i/ti_clocks)

Sources:
- [Wikipedia: Radiocarbon dating](https://en.wikipedia.org/wiki/Radiocarbon_dating)

Source: https://mapideas.org/i/q_hist_date · open on the map: https://mapideas.org/#q_hist_date