This fort can be made for a variety of different things outside (Airsoft, Paintball, Survival Improvised shelter or just for fun) I made this fort for airsoft and it has proven to be a fun, reliable fortress. This fort could also be used or modified to be used in a survival situation

Tools: ( I only needed a knife, you may need some of the following)
. Axe
. Shovel
. Multi tool
. Knife
. Rope

Materials:
. Branches
. Sticks
. Leaves
. Rocks
. Area with trees
Optional:
. Plywood or wooden pieces
. Tarps

Step 1: Finding a Good Location

Before we start building our fort, we must find a good place to build it, I found an area with trees spread apart.
This is very important because many factors of the location can affect the building and size of your fort.

Step 2: Gather Some Supplies

Start by gathering branches, leaves, logs, etc; anything that can help you build it, will be needed. Also the design of your fort may need you to acquire different materials. If you have a burn pile or a old wood pile there might be some good materials in them.

Step 3: Design / Building

After gathering different types of materials, it's time to plan the design of your fort, you could mentally design it or if you want a more detailed one you could take notes and create blue prints. You can you the method I used, which is filling in the gaps of the trees with sticks and logs. For a few of the gaps I had some plywood sitting around, since I'm making mine for airsoft this provides ideal cover from enemy fire.

Step 4: Finishing Touches

If you want to make your fort more camouflaged, you can take branches that have leaves and tie them around branches. After that you can hang the others ones through the ones that's tied and it acts as a holder. After placing many branches around it, you will have a camouflaged wall.

Step 5: Finished Product

The finished product might look a bit different then the one I show, depending on the materials you used or the design. This fort is pretty steady and long lasting, the leaves may dry up over time, but are are an easy fix and can be rebuilt.