For us & people who stay in Bangalore, it is 270 odd Kms and just 5-6 hours ride which makes it possible for us to go to Coorg for weekend getaway from Bangalore and cover all the places to visit in Coorg at our own pace.
For the rest of the world, the nearest airport to Coorg is in Mysore (120 Kms) and then comes Mangalore airport (135 kms). From Mysore airport it takes roughly 3 hours to reach Coorg by taxi. Nearest railhead is Mysore and you also have Hassan Railway Station at a distance of 146 Kms from Coorg.
The best part about driving down to Coorg is that overall it is a smooth ride. Most of the road is either 4 lane or 2 and there are literally no hairpin bends! Imagine having a puke-free ride to a hill station! It is a major relief for people like me who love traveling but are blessed with bad motion sickness!