I've just noticed an interesting anomaly on the Freedom
Pass Map which can be viewed on or downloaded from the
Internet.

On each route the last station within the Freedom Pass area is
shown with a grey line projecting onwards; the grey line being
a route where free travel is never available. Understandably,
no stations are designated on the grey lines.

There is a single, misleading exception: Cheshunt. The Freedom
Pass area ends at Enfield Lock and Turkey Street, and on TfL's
map the grey lines start from there. But Cheshunt is shown on
the map and, to those not perusing cautiously, this suggests
that Cheshunt is in the Area. I nearly got caught out this morning.

Why has TfL made this single exception?