Airways (1) Airways is the fastest and the costliest mode of transport. (2) It can cover very difficult terrains like high mountains, deserts, thick forests and long stretches of seas with great ease. (3) Due to the small carrying capacity, it is not suitable for carrying bulky, heavy and cheaper goods. (4)It is not environment-friendly. (5) Airways are classified into domestic  and international airways Waterways (1) It is cheaper and slower than the airways. (2) It provides access to very limited areas. (3) It is most suitable for carrying heavy and bulky goods. (4) It is environment-friendly. (5) Waterways are classified into inland waterways and ocean routes.