Grass floors can also be easily transformed into a home space. All you have to do is dig a hole in the floor according to the height you want for your fireplace and place bricks around the base and around it. Do not forget to add pebbles and stones so they do not slip.
If you have a spare tire at home, you can use the inner part as the base of your home. Of course, you will have to remove the rubber outer part of the tire. Otherwise, you will have the fumes of burned tires. Stack the concrete slabs around the fireplace to make them a bit better and cover the interior.
If you want a more decorative fireplace, try concrete blocks in two different colors. You can alternate them as in the photo to get a neater look. A two-level fireplace is even better, especially if you place some pebbles between the two circles.