In the biblical Noah's Ark story, how many cubits long was the ark?

In the biblical Noah's Ark story, the ark was 300 cubits long. Genesis 6:15 gives three dimensions: 300 cubits in length, 50 cubits in width, and 30 cubits in height. The text does not define the exact length of a cubit in the passage.

A cubit was an ancient unit commonly related to the distance from an elbow to a fingertip. Its practical length varied across cultures and periods. Depending on the cubit used, 300 cubits is often estimated at roughly 135 to 157 metres, but any modern conversion is approximate.

The dimensions produce a long, rectangular vessel rather than a conventional ship shape. Genesis also mentions three decks, rooms, a door in the side, and an opening near the top. Readers should therefore distinguish the stated biblical measurement from later artwork, which often gives the ark a more boat-like appearance than the text requires.