My wife and I use TWO lightweight collapsable walking sticks on hikes or long walks where there are steep uphills, downhills, stream crossing, rock hopping, or wherever we anticipate possible fatigue, poor footing, or dangerous animals. They're indispensible for nudging rattlesnakes off the trail, or making yourself look (and be) menacing for cougars in the wilderness (both are real possibilities in the backcountry of Southern California) or to discourage dogs in the city.

Using two sticks allows equal stress relief on both legs and equal exercise and development for both sides of the upper body.

This is to show what ours look like: http://www.rei.com/online/store/Prod...cat=REI_SEARCH
We got REI brand at 1/2 price on sale. That's a recommendation, but there are many other good brands, and many are less expensive. In good trekking poles look for strong and sturdy, quiet, easy to use, lightweight, and adjustable. Most come with carbide tips, but take removable rubber tips for concrete, and snow baskets for winter. They should last a lifetime of walking.