The use of latest technologies to curb the menace of traffic congestion and environmental problems like pollution, increase in GHG emissions etc., is in practice in such a way that the outcome results in sustainable transportation. One such idea is CarTube. This review paper is about how CarTube can help in the decrease of traffic problems and make long distance travels speedy and less costly. This article also puts light on the facts that why this particular concept is said to be hypothetical and mythical by some experts. This paper will help budding engineers and transportation planners to get familiar with the concept of how successful or unsuccessful the CarTubes would be, with all the reasons.