The Ages

The precession of the equinoxes

The equinox drifts backward through the zodiac about one degree every 72 years — a full circle (a "Great Year") in ~25,772 years, divided into twelve Great Ages of ~2,150 years. We stand in the Age of Pisces: the outgoing age; the Aquarian dawn is near but its exact boundary is disputed.

Other reckonings (expanding)

• The classical Ages — Golden, Silver, Bronze, Heroic, Iron (Hesiod).
• The Yugas — Satya, Treta, Dvapara, Kali (the great Hindu cycle).
• Geologic & archaeological ages — Stone, Bronze, Iron; and the epochs of deep time.
• Chain time — block height as a ledger's own calendar.

Each of these gets its own computed/annotated section as the Almanack grows.