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.
Trans-Siberian Highway. The 11,000km long Trans-Siberian Highway is the world's third longest highway. It stretches from St. Petersburg to Vladivostok in Russia. The section of the route spanning the Asian Highway Network is called the AH6.