The World Data File starts with a Header Section which contains:

Offset Size Data Description

0000 ID 46 00 00 10 UID1: World Data File

0004 ID 00 00 00 00 UID2: Unused

0008 ID 00 00 00 00 UID3: Unused

000C L F1 E7 5A 04 UID4: Checksum of UID1, UID2 and UID3

0010

The remaining file is structured as follows:

Size Data Description

L 01 00 00 00 Marker to start the city section

LListE World Data City Section

L 00 00 00 00 Marker to start the country section

LListE World Data Country Section

String New city name

String New country name

String Original city name (empty string if this is a new city)

String Original country name (empty string if this is a new city)

8B City data

String Area code

The city data is very compact, probably to save space:

Start End Description

0000 bit 0 0001 bit 0 Horizontal map position (left=000, right=17b)

0001 bit 1 0001 bit 2 Unused?

0001 bit 3 0002 bit 7 Latitude in minutes (South is negative)

0003 bit 0 0003 bit 7 Vertical map position (top=00, bottom=cf)

0004 bit 0 0005 bit 6 Longitude in minutes (East is negative)

0005 bit 7 0007 bit 1 GMT offset in minutes

0007 bit 2 0007 bit 3 Summertime zone (0=none,1=europe, 2=northern, 3=southern)

0007 bit 4 0007 bit 7 Unused?

Longitude, Latitude and GMT offsets are encoded as Signed Integers,

Note that if you change the name of a country, all its cities are also put into the World Data City Section.

Country section elements are structured as follows:

Size Description

String New capital city name

String New country name

String Original country name (empty string if this is a new country)

String National code

String National prefix

String International prefix