Overview. If you frequently experience shortness of breath or you hear a whistling or wheezy sound in your chest when you breathe, you may have asthma â a chronic condition that causes inflammation and narrowing of the bronchial tubes, the passageways that allow air to enter and leave the lungs.
1 At 47,958 kilometres (29,800 miles) in total length, the Pan-American Highway is the longest road in the world.  The road starts in Alaska, North America and ends in the lower reaches of South America.
The longest Interstate is I-90, traveling from Seattle, WA to Boston, MA over 13 states for a total distance of 3,020.54 miles. On the other end of the spectrum is Interstate 97, the shortest mainline Interstate.