According to Genesis, what was the Ark's longest stated dimension?

According to Genesis, the Ark's longest stated dimension was 300 cubits. Genesis 6:15 gives the vessel's measurements as 300 cubits long, 50 cubits wide, and 30 cubits high.

A cubit was an ancient unit based broadly on the length of a forearm, so its exact value varied by culture and period. Using a commonly cited estimate of about 45 centimetres, 300 cubits would be roughly 135 metres. That conversion is approximate because Genesis does not define the cubit used in the passage.

The proportions produce a long, box-like vessel: its length was six times its width and ten times its height. Those ratios have attracted attention from naval and engineering writers, but the biblical text does not present the ark as a conventional sailing ship. It gives no sails, rudder, or propulsion system; the vessel's purpose is survival and flotation rather than navigation.