How to Make a Snow Igloo

Find a good spot. The key ingredient to a stable igloo is hard snow. Good snowball snow won't do. You're looking for a field of snow that necessitates a shovel to break through and a saw to cut. Don't panic if the snow on the top is soft -- often the snow underneath will be nice and hard. Make sure you are wearing good waterproof snow gloves.

Use your snow shovel to mark a circle in the snow, about eight feet across. This will be your igloo's base circle.

Dig three feet in depth, straight down from your base circle line. The snow shovel should be able to penetrate much of the top layer of snow, while the snow saw should be able clear out the rest. As you are clearing this snow, be sure to cut the snow into rectangular blocks one to three feet in length and a foot to a foot and a half in width and height. Place these blocks on the snow outside of the base circle line. They'll be used later. Make sure at least one of these blocks is around three feet long. Continue until you've completely cleared all the snow from within the base-circle line to a depth of three feet. You should now have not only a well-dug, eight-foot-wide hole, but also a large supply of snow-saw-cut blocks.

Dig a two- to three-foot-wide, six-foot-long entryway, also three feet deep, coming out of the hole. This will serve as your entrance. The fact that it is essentially below ground will shield you from the worst of the wind -- and provide a quick escape route should your igloo collapse for some reason.

Using the longest blocks, encircle the base circle. Be sure to place a long block of snow over your entrance (see Step 4). This is your bottom layer of blocks. Continue stacking blocks onto each other, longest toward the bottom and shortest toward the top, leaning the blocks slightly inward with each level until the layers meet (typically at the sixth or seventh layer) at a central point on top. All the while, you can use the softer snow all around to pack around the blocks -- like cement, pressed into the spaces between blocks. This will both hold the blocks together as a natural adhesive and also prevent wind from penetrating your igloo.

Create your cork block. This will be the piece that goes on the very top of your igloo, in the center -- the keystone. Be sure it is larger than the opening at your igloo's top, and cut the sides with the snow saw so that it tapers to fit the angle of your igloo. Slowly place it onto the top of your igloo, again employing soft snow as a kind of cement.