Police say metal detectors deter knife-carrying people
Crime has fallen 11% on London Underground, figures from British Transport Police (BTP) have shown.
The annual figures also show violent crime is down 4.4% at railway stations in the north of London and has reduced by 14.2% at stations in the south.
Robberies on the Tube are down 51%, while knife crime on mainline stations has been cut from a mid-2006 peak of about 70 every month, to about 20.
But drug and fraud offences are up on both the Tube and railways.
Robberies on mainline stations were down but public order offences were also up on stations in the south of London.
The Mayor of London Boris Johnson welcomed the results, saying: "The transport network plays an important role in the lives of millions of Londoners, and it is essential that the Tubes and trains are places where we can all go without the fear of crime.
"Unfortunately many Londoners do not feel as safe as they should do when using the network, which is why we have made tackling transport crime one of our number one priorities."
The drop in knife crime on the railways has been attributed to scanners being deployed at stations.
Senior officers said 244 knife arches and 550 scanners are now in use across London as police try to take potentially lethal weapons off the streets.
BTP chief constable Ian Johnston said the portable units have helped make railways a no-go zone for people carrying knives.
"The reason we do not get very much knife crime is that people know they are taking a risk turning up with a knife.
"The visual impact is important. We give a very clear message that we do not tolerate this.
"We do not catch people going through the arches with knives. What we catch is a lot of people seeing them and walking away."