Brain-Teaser 489

From The Sunday Times, 11th October 1970 [link]

The All-Go railway runs from Alby to Goby over 20 miles away. Let us say it goes from A to G, and on the way you stop at B, C, D, E and F in that order.

All the distances between stops are different from one another and all are less than 8 miles, yet it is possible to make journeys of 1 mile, 2 miles, 3 miles and so on up to 18 miles by picking the right stations.

The distance from A to B is less than the distance from F to G.

How many miles from A are B, C, D, E, F and G?