The largest in historic times was the result of the Good Friday earthquake in Alaska in 1964, and destroyed part of downtown Port Alberni.

[6] Tsunamis repeatedly hit the First Nations village Huu-ay-aht of Sarita, which is on a low sand beach about halfway along the inlet's eastern shore.

As described by the BC Geographical Names Information System: First labelled Canal de Alberni on Spanish charts.

Despite the shallow depth of the sill midway up the inlet, deep water in both basins is renewed annually, a process driven by upwelling in the ocean to the west of Vancouver Island.

[9] Alberti Inlet is a fjord cut by an outlet glacier draining from Pleistocene-age ice caps in the mountainous interior of Vancouver Island and later flooded during the sea level rise at the end of the Last Glacial Maximum.

[9] After these events, Wrangellia accreted to the North American Plate along the west coast of the continent from Vancouver Island to what is now Alaska.