From the Traveller RPG wiki on wikia.com:
In the first issue of The Travellers' Digest, a series of adventures called The Grand Tour was kicked off. The plan was to tour the entire Imperium, from the Spinward Marches, to the Solomani Rim, and back. From the start, the Tour went off well. The adventures slowly moved across the Imperium, uncovering pages of background material on each subsequent sector as it did. Near the end of 1990, the Grand Tour finally came to an end in the twenty-first, and final, issue of the Travellers' Digest.