Cobblestone is a form of granite or basalt that makes for a strong walkway. You may use either rounded top stones or flat stones for the surface of the sidewalk, but flat stones may be easier to navigate on foot. Cobblestones can last as long as cement. Keep a close eye on the mortar between the stones for cracking. If you notice cracks, repair them as soon as possible to prevent severe damage.
Brick is a material commonly used to pave sidewalks before the first use of cement in the United States. If you live in old cities with historical districts, it is likely you still will see many sidewalks composed of brick. In most cases, brick can outlast cement, but brick is not as flexible. Cement fills an area when poured, while you carefully have to lay out bricks or cut them to have them properly fill a space.
Wood doesn't last as long as cement, but with a little work and a lot of care, you can make wood last a reasonable amount of time. Wooden planks may result in a classy sidewalk. Use different treatments and stains on the wood to get different colors to suit your taste. Wood ultimately is a soft material, so it is important to change the planks when you notice extensive damage or wear occurring.
Asphalt is a mixture of gravel and sand that results in a tough substance akin to dried tar. While you may think of paved roads when you think of asphalt, the material makes an effective alternative to cement. Asphalt is cost-effective, but requires a little more maintenance. One of the benefits of asphalt is its craggy surface; the rough surface gives the sidewalk traction on rainy days.