Library.

“Viking ships were built using the clinker-building method with overlapping planks, which made them lightweight, durable, and flexible in rough seas.”

The evidence strongly supports this description of Viking shipbuilding. Major museum and reference sources agree that Viking ships were clinker-built with overlapping planks, a method that created light, strong hulls with enough flexibility to handle rough water well. The main caveat is that scholars debate whether that flexibility was intentionally engineered or emerged as a consequence of lightweight construction.

“Viking ships had shallow draughts that allowed them to navigate up narrow rivers and to be beached directly on coastlines for surprise attacks.”

The evidence strongly supports this description of Viking longships. Authoritative museum, archaeological, and reference sources consistently state that their shallow draught and light construction let them travel in shallow water, move up rivers, and be beached directly for rapid landings, which helped make raids more sudden and flexible.