There are many ways to build walkways, you can use different types of gravel, pavers, travertine, natural cut stones, porcelain pavers, flagstone, concrete blocks, or granite gravel. Bases can be constructed of granite gravel, or concrete bases for mortar set with flagstone and natural cut stone. Stepping stones of the same materials or combinations of say gravel and stepping stones. Stepping stones can also be set flush with grass using a granite base after excavation.