The largest island in a lake on an island in a lake on an island is a nameless 1.6-hectare (4-acre) island at 69Â°47â²35â³N 108Â°14â²28â³W / 69.793Â°N 108.241Â°W / 69.793; -108.241, 121 kilometres (75 mi) inland from the south coast of Victoria Island, Canada.
A tsunami can travel across the open ocean at about 500-miles per hour, the speed of a jet airliner. As the wave approaches land and as the ocean shallows, the wave slows down to about 30 miles-per-hour and grows significantly in height (amplitude).
The Canary Island scenario, in my opinion, might yield less energy relative to how fast it travels, wave height, how far inland, etc. the tsunami travels, however, a more intense event, like an asteroid, meteor, or other object splashing into the Atlantic would probably garner much more energy, wave height, and moving the tsunami much further inland.