Man-made fibres are to be distinguished from natural fibres such as silk, cotton, and wool. Natural fibres also consist of polymers (in this case, biologically produced compounds such as cellulose and protein), but they emerge from the textile manufacturing process in a relatively unaltered state. Some man-made fibres, too, are derived from naturally occurring polymers.
Mount Si is located in North Bend, Washington (USA). The climb is 4,167 feet (1,270 meters) and 4 miles from the parking lot to the summit plateau. Vertical elevation change is about 3700 feet and starts at about 700 feet. The route meanders through several different ecosystems as temperatures and average rainfall vary with elevation.
Head 0.5 miles on 436 Ave SE and take a left on SE North Bend Way. Proceed 0.3 miles and turn right on SE Mount Si Road. The main parking lot for Little Si will be 0.4 miles on your left as the road straightens out after the bend (if you pass 439 Pl SE or 440 PL SE, you have driven too far).