Take a moment, if you will, and try and enumerate the seven wonders of the world. Chances are that you'll be hard pushed to get beyond four or five. We stumbled before we were half way. Antipater of Sidon, a Greek composer of witty epigrams, put pen to paper and described the structures in about 140 BC. It is likely he was drawing on earlier lists - but they haven't survived, so Antipater of Sidon gets our vote as a classical forerunner of Baedeker.
Those seven wonders are clustered within a small part of the world. Six are in the east Mediterranean region, and only Babylon (not far from modern Baghdad) seems a tad far flung. The assiduous traveller of ancient times might, with a little careful planning, have managed to visit six wonders (all bar Babylon) within the space of a week's vacation.
Fate has not been kind to the seven ancient wonders. Two had suffered grievous damage even by the time Antipater of Sidon compiled his list. A young vandal called Herostratus had set fire to the Temple of Artemis, and the Colossus of Rhodes had been toppled by an earthquake.