Sexual offences on the Metropolitan line nearly doubled last year, amid a 44% rise across the Tube network.
The number of such crimes reported on the line rose to 47 last year from 24 in 2014 - an increase of 96%.
There were also sharp rises on the Central (46%) and Circle (43%) lines, exclusive analysis of figures obtained under the Freedom of Information Act for getwestlondon reveals.
In total, 774 cases were reported to police last year, compared with 536 in 2014.
The biggest percentage increase was on the Northern line, where the number of offences recorded rose from 58 to 119 - a 105% increase.
Central line saw most sexual offences last year
The Central line saw the most sexual crimes recorded last year of any line, with the number rising from 132 to 193.
British Transport Police attributed the high number of crimes on the line to the fact it has 49 stations and carries 15% of the Tube's total volume of passengers.
A BTP spokesman said: "Many of these stations are busy hubs with huge numbers of people passing through, so the numbers of offences are always likely to be higher than at smaller stations.
"Larger, busier stations also have a higher police presence, so more offences are likely to be recorded as a result of police-generated activity."
Police last year put the high number of sexual offences on the Central line down to crime-detection "challenges", including the lack of CCTV on some trains.
"It has the old rolling stock and does not have CCTV... These are some of the challenges we face but it does not stop us detecting things like pickpocketing or sexual offences," Superintendent Chris Horton of BTP told the International Business Times.
Sexual offences on the Tube
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