According to the Oyster menu on Southern TVMs,

the unadvertised zone for Broxbourne and Brentwood is zone 11,
and the unadvertised zone for Shenfield is zone 12.

A Zone 1 - 12 travelcard would seem to include Watford Junction (which
is the unadvertised Zone 10), but probably not the lines to Grays.

The Oyster menu on other TOCs TVMs just seem to display a blank
instead of a number.

In message , at 01:02:38 on
Sat, 19 Jan 2013, Matthew Dickinson
remarked:
According to the Oyster menu on Southern TVMs,

the unadvertised zone for Broxbourne and Brentwood is zone 11,
and the unadvertised zone for Shenfield is zone 12.

A Zone 1 - 12 travelcard would seem to include Watford Junction (which
is the unadvertised Zone 10), but probably not the lines to Grays.

Is a Brentwood Travelcard actually valid for everywhere Z1-11, or is it
just valid in z1-6, plus the trip from BZ6 to Brentwood?

Which would make it rather like an out-boundary travelcard, I agree.
--
Roland Perry

On 19/01/2013 09:44, Roland Perry wrote:

Is a Brentwood Travelcard actually valid for everywhere Z1-11, or is it
just valid in z1-6, plus the trip from BZ6 to Brentwood?

It depends on who you ask, as does the price!

According to TfL a Day Travelcard for Zones 1-9 + Shenfield should be
£17.80 Off-Peak or £26.20 Peak; Zones 1-9 + Brentwood or 1-9 +
Broxbourne should be £16.20 Off-Peak or £22.90 Peak; and Theobalds
Grove, Waltham Cross and Cheshunt should take the Zones 1-9 price of
£12.10 Off-Peak or £20.40 Peak.

According to Avantix Traveller for NFM14, however, a Day Travelcard from
all of the aforementioned station only has validity in Zones 1 to 6, not
7-9, and prices are £20.40/£26.20 for Shenfield (which also has a £16.40
Super Off-Peak), £17.80/£22.70 for Brentwood (£15.90/£25.10 for tickets
routed via Shenfield!), £19.00/£24.00 for Broxbourne, £16.40/£19.50 for
Cheshunt, and £14.10/£19.50 for Theobalds Grove and Waltham Cross.

Chiltern WebTIS gives £20.40/£26.20 for Shenfield, £17.80/£22.70 (and
£15.90/£25.10) for Brentwood, £18.20/£24.00 for Broxbourne,
£15.70/£21.10 for Cheshunt, £14.10/£20.20 for Theobalds Grove, and
£15.80/£21.20 for Waltham Cross.

Hopefully an e-mail to Greater Anglia Customer Services will result in a
definitive answer!

Cheers,

Barry