The 311 tsunami in Kesennuma city in Miyagi Prefecture, Japan.

Notes:
In this video, you can see how the tsunami first ascends the Okawa river in Kesennuma city, and then spills over the embankment, flooding the town. Debris and buildings nearer to the harbor are carried further inlands.
The mouth of the river is nearly two kilometres away from the location from which the video was shot.

00:10 — The tsunamis wave trough, which was arriving first, has drained the river
01:45 — The tsunamis first wave is appearing and steadily ascending the river, probably a couple of metres high
05:00 — While the wand of water rushes by, smoke appears over the harbor — the tsunamis moving inland by now
05:45 — The water is rising steadily and the people recognize the danger. A police or civil defense man urges all people to evacuate to the school building behind because the tsunami has overcome the harbors seawalls. He keeps warning the community using a loudspeaker
07:00 — The cameraman enters the schools emergency staircase just in time. While still climbing, the water behind him overcomes the rivers embankment and flows onto the school grounds
08:15 — A large wave of debris can be seen approaching from the harbor, simultaneously, the tsunami smashes the passenger bridge next to the school to pieces
09:30 — Large debris, buildings and such arrive at the school. The flooding intensifies. During the next ten minutes, the school ground is flooded with debris and water.
19:15 — The tsunami stops and starts receding. The following shots are filmed at different times and show the large fire which further devastated the harbor and more (but considerably smaller) waves coming in, hours after the first (since its nearly dark by then).

I didnt shoot this video, it was shot by Mr. Kenichi Kurakami.