This is some basic information that I believe will really help those who are interested in a world time watch not only for its beauty but also its functionality.  It's amazing what you can learn from just looking at pictures of the watch, however at first this is not intuitive, hence this guide was created from bits of information I've gathered and watches I own.  Keep in mind that this may not be 100% correct, but for all the watches that I've seen (more than 100 unique types) it is.  Also feel free to ask the watch seller specifics about their watch, although in about 60% of these cases I've found that they don't know much about the watch they are selling, or give erroneous information.  If you doubt what they tell you, ask them to take pictures of the watch in specific settings that will more accurately show how it operates.

The way this works is that you start from the top, and if the watch you are looking at satisfies the Question then the following Yes applies to this watch, otherwise go to the next No.

To begin with, the watch at a very minimum has a 24 hour bezel on it (a ring with all the hours of the day), a city bezel (a ring with cities from most if not all the time zones listed on it) and is 100% analog.

- Question -

Does the 24 hour bezel have the same time at the top (12 o'clock position) as the current time (i.e. it says 10 o'clock on the analog hands and the number on the 24 hour bezel at the top is either 10 or 22)?

- Yes -

I personally think this is the best type of watch, as the 24 hour bezel rotates automatically as time passes and does not need to be set by hand when you wish to see the time in another timezone.

With this watch you rotate the home city on the city bezel to the top (12 o'clock) position and from then on can see the time in any timezone (city.)

Hamilton world time 'power' is one such watch that is quartz (battery powered) watch with date which has the hours laid out nicely, incrementing clockwise and the daytime hours are light and night time hours are dark.

(picture of Hamilton world time with home city of Chicago at the top, note that it's 1:54 on the analog hands and on the 24 hour bezel at the top)

Another watch of this type is the Marco Polo mechanical (hand wound) world time automatic (motion maintained, as you move it keeps the watch wound) but with the hours incrementing counter-clockwise, and no date.

(picture of Marco Polo mechanical world time, note home city of New York and analog 10:12 matching 24 hour bezel)

Note that quartz watches (battery powered) do not need constant winding as do mechanical watches, and also quartz watches tend to be thinner and more accurate than their automatic counterparts, however mechanicals will often times have a clear back to see the internals of the watch.

------------------------------------------- No -------------------------------------------

- Question -

Does the watch have a GMT hour hand?

- or -

Is the analog time not set at midnight/noon and the hour bezel has 24 or 0 or a symbol at the top (12 o'clock) position?

- or -

Does the date cut into the hour bezel?

(picture of Marco Polo watch that has GMT hand [black hand pointing toward the right at just after 6, apparently set independent of the analog time], analog time set to 9:10 but 24 hour bezel has 24 at the top, and date cutting into 24 hour bezel thus it does not rotate)

- or -

Does the 24 hour bezel have the numbers at the top (12 o'clock) and bottom (6 o'clock) oriented upright as you look at them (vs. upright at the top [12 o'clock]and upside at the bottom [6 o'clock])?

(picture of Orient World Time with the date cutting into 24 hour bezel and the 24 hour bezel numbers on bottom oriented upright )

- Yes to any of those questions -

Most watches fall into this category.

You check the time in another time zone by rotating the city bezel such that the current city matches the current time (in the case of a GMT watch just line the GMT city up with the GMT hand) on the 24 hour bezel and then find the time in another city (very small chance that the city bezel may rotate automatically.)  The 24 hour bezel does not rotate at all (very small chance that it might, if it does or if the GMT hand can be set independently then the watch becomes a dual time/world time watch, otherwise the GMT hand points to the same time on the 24 hour bezel as the analog hands.)  I don't care for this type of watch since it requires work on the wearers part.

------------------------------------------- No -------------------------------------------

All the rest of the watches should fall into this category.

The watch has a crown that rotates the 24 hour bezel independently from the current time, and it may or may not rotate automatically.  You check the time by rotating the 24 hour bezel to the current home city time and then find the time in another city.  Most likely the city bezel is fixed (GMT near top and/or cities text oriented correctly at bottom.)  This has the potential to be the best type of watch, but there are too many uncertainties with the world time mechanism and so much confusion among the sellers that I tend to stay away.

CTI 3008 mechanical series dual/world time does rotate the 24 hour bezel automatically and independently, however the city bezel is fixed and the cities on the city bezel are oriented in reverse!  Hopefully they will release a corrected city bezel to fix this oversight and make this the watch it was intended to be, otherwise as it stands now this is a dual time watch only.

 (picture of CTI 3008, note that from Los Angeles to New York the hours should be incrementing, and not decrementing, the reason being is that it mimics a Patek [see following picture], however when they reversed the 24 hour bezel [because it now rotates clockwise instead of counter-clockwise as in the Patek] they failed to reverse the city order to match.)

(picture of Patek Philippe world time which is very similar to the CTI above)

(two pictures of Marco Polo world traveler GMT, notice that both the city and the hour bezel rotate independently [different in each picture] giving it the dual time/world time function [I'm not sure if the cities rotate automatically.])

Here are some world time watch companies:

CTI (very difficult site to find, had to call to confirm) unitedwatch.com

Hamilton (seems to be out of the world time watch business)

Marco Polo marcopolowatches.com

This guide is your guide, I spread this information hoping that it will make for a more informed public, and hopefully better watches!