It is not only possible to enjoy camping without a tent. Some people prefer not to have to carry a tent around with them. They make use of other shelter and sleeping systems.
The most basic way is to carry a tarp — just a waterproof flysheet — to keep off the rain. And when you add a small sheet of plastic or other waterproof material underneath your sleeping bag, you are ready for a good night’s sleep. You had just better pick a location without insects!
Soldiers used to call it bivouacking down for the night (from the French word bivouac). Today’s troops refer to this kind of make-do army shelter as a Basha (UK slang) or a Hootchie (US slang).
Some campers prefer to use a camping hammock instead of a tent. These hammocks are pretty small and convenient to carry, can be set up and taken down again quite fast, and they keep off the rain and the keep out the bugs as well. You can also use them in places where a tent would never work — such over boulders or across a running stream!
The most lightweight way of camping without a tent is to use a waterproof bivy bag. (Some spell it bivvy bag, but who really cares?) Slip your sleeping bag inside, and the bivy bag will keep out the rain and will stop the damp rising from the cold earth below you.
Tarp Camping
Many lightweight campers like to leave the tent behind and camp with a tarp (a waterproof tarpaulin) above and a waterproof ground cloth below.
Hammock Camping
Camping tents won’t pitch just anywhere. They need a fairly flat area of ground to be staked out on. A hammock will let you camp on slopes and rocky areas… and all you need is a couple of trees or posts.
Bivvy Bag Camping
A bivvy bag is a lightweight, waterproof bag that you put your sleeping bag into for sleeping outdoors without a tent.