Cubit

tourguide
A cubit is an ancient unit of length based on the forearm, measuring from the elbow to the tip of the middle finger, generally accepted as approximately 18 inches (45.7 cm). While varying by region and era, it was commonly divided into 6 palms or 24 digits. The Egyptian Royal Cubit was longer, about 20.6 inches (52.5 cm).
Common Cubit: ~17.5–18 inches (44.5–46 cm).
Royal/Long Cubit: ~19.8–20.6 inches (50–52.5 cm).
Origins: Used by ancient Egyptians, Babylonians, and Israelites; dating back nearly 5,000 years.
Bible References: Noah’s Ark, Goliath’s height, and temple measurements are given in cubits.
Modern Equivalence: Roughly 1.5 feet or a half meter.–Gemini

tour guide down the street from Diocletian’s Palace, Split