Though London Underground network can be quite confusing to the tourists. After plying through the same routes on a daily basis, one would probably not have to rely on the map after being in London for a couple of weeks.
I remember when I first come to London, I used to have a Tube map handily tucked in my pocket. Gradually, as I become more familiar with the network, I no longer find it necessary to carry a Tube around and scoffed at those who still does .
Some time back, I stumbled upon some Tube maps being auctioned on EBay. One 1937 London Underground map was going at over £23 (exclude postage) while the 1964 version was going for just under £7. It was not exactly a king's ransom but considering that it was given out for free back then, the returns were mathematically infinite.
For those of us who are hoping to fund our retirement with these Tube maps, hope is still in sight. The London Underground is currently publishing Tube maps on a quarterly basis with a new design each time round. So the next time you past by the Tube ticket booth, grab some maps. Who knows? They may just worth a fortune a couple of decades down the road.