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Timeline of the Hitch-Hiker Canon (General evidence)

Because of the extensive time-traveling and frequent backstories that take place in the HHGtG Series, one individual timeline would be very fragmented. For example, some events in Life, the Universe, and Everything take place over two billion years before the original destruction of Earth. Another similar circumstance is that during Arthur and Ford's five-year exile on Prehistoric Earth, only a day or so seems to pass for Trillian and Zaphod. So there are two timelines in this article. The first one takes place from the viewpoint of Arthur Dent. The second one takes place from the viewpoint of the Universe in general. The destruction of Earth in Book I is used as a reference point for both timelines. Based upon the evidence in Book III, the Destruction of Earth takes place sometime in the early 1980's. Be aware that all values are approximate. Some events in this timeline are based on the radio series and a visual timeline of such can be found here.

BDE Before Destruction of Earth
ADE After Destruction of Earth
H, D, W, M, Y Hours, Days, Weeks, Months, Years

Timeline from Arthur Dent's point of view.

Event Book Date
Arthur meets Ford Prefect for the first time N/A 5Y BDE
Arthur meets Trillian (Tricia McMillan at that time) at a party in Islington. He fails to impress her, and she runs off with Zaphod Beeblebrox. N/A 6M BDE
Arthur first learns of the impending destruction of his house at the planning department. N/A 18H BDE
The next morning, Arthur wakes up to find a bulldozer outside of his house. He lies down in front of it, and halts the destruction of his house. I 5H BDE
Ford arrives at the scene, and takes Arthur with him to the local pub. Ford convinces L. Prosser, the foreman, to take Arthur's place in the mud. I 1H BDE
The Vogons arrive to destroy Earth, and Ford rushes Arthur back to his house, which has been knocked down. The two beam themselves up to the Vogon Ship at the last second, leaving Earth to its fate. I 0 BDE/ADE
The Vogons torture Arthur and Ford with Vogon poetry, then throw them out of the airlock soon after. Then they land on the Heart of Gold. I 2H ADE
They arrive at Magrathea by way of the IID. A bowl of petunias and a sperm whale crash-land into the planet. I 3.5H ADE
Arthur meets Slartibartfast, designer of the Norwegian fjords. Arthur goes with him in an air-car to the planet's interior. I 3.5-4H ADE
Arthur learns of the meaning of life = 42. They later meet at dinner with the two white lab mice discussing the meaning of life. I 4.5H ADE
The group re-enter the Heart of Gold and travel to the Restaurant at the End of the Universe. II 6H ADE
At the Haggunenon Flagship, the group split: Ford and Arthur with Zaphod, Trillian and Marvin. II 9H ADE
The Escape Capsule. (in need of a better description.) II 11.5H ADE
Prehistoric Earth. Arthur is trapped in the building of Earth, 2 million years before the beginning of the story. II-III 14H-5Y ADE
Two universes split. Hereafter there is the 'standard' progression, and Zarniwoop's Artificial Universe (noted here as ZA). III 5Y ADE
ZA: The Starship Heart of Gold. Zaphod and Marvin meet up with Ford and Arthur. III 5Y ADE
ZA: Brontitall (Nutrimatic Cup, Arthur's Statue's Ear). At Ground level, Ford leaves Arthur. III 5Y ADE
ZA: Dolmansaxlil Base: Lintilla and Allitnil. III 5Y ADE
ZA: The Starship Heart of Gold. III 5Y ADE