The maps below show:

[The
West Sussex map is adapted from a map kindly provided by
WSCC.]

The
third map shows a
large-scale version of the location of the Peninsula with Chichester
and Pagham Harbours.
[Map reproduced by
permission of Ordnance Survey, © Crown copyright.]
This map can be downloaded from the Ordnance Survey "Get-a-Map" website service where larger scale versions are also available. The map is centered on the UK grid reference position SZ 834 989.
It should be noted that the name "Manhood Peninsula" is widely used and recognised locally but does not appear on any official maps issued by the UK Ordnance Survey.
The name is believed to be ancient, probably of Saxon origin. It is used by all local government bodies including Chichester District Council which includes the Peninsula within its administrative area, West Sussex County Council and the South East England Regional Assembly.