Some of you might have heard about going on Sub-24hour-Overnight trips. Basically you leave one afternoon, cycle to a camp-site, camp out, and cycle home in the morning. It's a great way to prepare yourself for cycle touring. Since you are committed to only one night out, if you forget to pack anything, or find your equipment lacking in any way, you know that the following night you will be home and can enjoy all your home comforts again. Since you're only packing for one night, you don't need as much food, clothing and camp equipment as you would for a multi-day trip. Typically, you should be able to pack for an S24O on a large pair of rear panniers, a handlebar bag, and strap your tent or sleeping mat to the top of your rear rack. It's also a good preparation for short multi-day trips of say less than a week, as it lets you have an appreciation of just how little you really do need to travel.
This works out great if you live within a reasonable distance of a camp-ground, say less than 30 miles or 45 kilometres. However, if you live in a big city like me (I live in Sydney's South-Western Suburbs), then it's a bit of a problem. There is a camping place about 45 kilometres from my home, but it does take some 3 or 4 hours to cycle there (the last 10km is just a series of steep hills), and the gates to the place close at 7:30pm, so one must leave no later than 3pm to get there. If you need to take a train trip for a leap-frog to a better starting point, then it's probably something you would best do on a Saturday morning, and return by Sunday afternoon (hopefully in time to catch the Sunday evening church service).