Select natural stone for the construction of the bridge. All decorative elements such as bridges or lanterns are made of natural materials. In the karesansui garden style, these bridges may be made of flat slabs of stone. Ideal stones are weathered rock in light or dark gray tones with lichen on them.
Measure the length of the stone slab. Measure and mark the location where the bridge will be in the zen garden based on this slab.
Dig out trenches for the stones in the crushed granite of the zen garden. The trenches should extend all the way to the landscaping cloth beneath the gravel. Ensure the base of each trench is flat, using a carpenter's level.
Set each 3-foot square stone flat in the trench. Fill in spaces around the stones with crushed gravel.
Stack the flat slab of stone over the top of the four smaller stones. The flat stone should be set so that it does not rock.