Green taxis (as I write on the warnings and dangers tip) can be dangerous, but if you have to take one just make sure to look at the ID card of the driver.
In Mexico taxis (specially green ones) are not expensive, just try to not look very "tourist" and know exactly were are you going and the adress, You will not find a driver who speaks english...
Taxis operate under distinct sets of rules.
For example, there are about 85,000 metered taxis everywhere in the city. They are mainly green or white/red VW 'beetle' that have white plastic roof signs bearing the word TAXI and TAXI painted on the doors.
These taxis operate strictly by the meter (taxímetro). If the driver says his meter isn't working, find another taxi.
Usually you may hire a gouging driver, or one who drives farther than necessary or applies other tricks/cheats to run up the tab.
Riding a taxi in Mexico City couldn't be a good idea if you think there are more than 4,000,000 cars fighting to pass first.
Metered taxis are essential for many people getting around the overcrowded city. They dart in and out of traffic with great ease, all for a good price.
But they are frequently involved in crimes against passengers. Virtually everybody here in this metropolis knows someone who has been held up at gunpoint in a taxi!
Taxi driver is also a dangerous profession in Mexico City, they are often the victims of assaults or even murders.
Homicide is not part of the routine, though beatings are common.
The governments of the US, UK, Canada, and Australia warn visitors against flagging down a taxi on the street.
As a tourist, perhaps your most serious crime problem here is taxi robbery.
This problem is more or less unique to Mexico City, so many forign tourists aren't aware of the problem.
Well, anybody who lives in Mexico City knows that taxi robberies are a problem, and takes certain precautions to prevent themselves becoming a victim.
The exact recommendations for residents and tourist may vary, but it is unwise to ignore the problem.
Any case, never forget that there are thousands of 'pirate' taxis (painted in green or yellow!).
IMPORTANT: If you do decide hire a taxi in Mexico City, read your correspondent government travel advisories about taxi cabs before you arrive, because taxi crime in the city is real.
The green taxis in Mexico City have a perfectly well deserved bad reputation - I have heard countless stories of Mexicans and foreigners who have been mugged, kidnapped and otherwise mistreated in one of these thousands of VW beetle patrolling the city streets.
There is only one problem: in many places unless you have a car the green taxi ("vocho") is your only option. Here are a few suggestions to improve your chances of surviving your "vocho encounters":
1. Preferably take a vocho if you know where you are going and that place is safe. Be aware of the streets the driver take - you don't want to end up in a blind alley in Azcapotzalco in a vocho.
2. Make sure the cab has a visible number (written in big black letters on the car) and the driver has a license (special plastic document showing the driver's photo and ID details).
3. If you can, try to take a vocho that has just dropped someone and with a driver who's at least 70 (don't laugh - it does increase your chance to run away in case of trouble :)
4. Vochos with an "S" number plate - "S" meaning "sitio" - are generally safe - but will not stop for you in the street. Get them at a taxi rank.
The police has started (2003) to make more and more verifications to remove rogue taxis from the streets. Hopefully in 10 to 15 years it will be possible to hail any cab in the streets of Mexico City :)
To take a taxi ride with one of the green vw's is quite cheap. Just make sure the driver turns on the taximetro or gives you a price in advance (at night). The green micros (little vans) are a fun way to get from one place to another. Just ask the local people for advice. They stop whenever you want them to. It's most of the time quite crowded but a great experience!
Well, there are plenty, of those green Volkswagen Beetle taxis. Best is to ask at the hotel reception to call for a taxi, that way it is safer. Because it can be dangerous, to take a taxi along the road specially when you are travelling alone, there have been many ripp-offs in the past. This picture was made from the 44th floor of the Torre Latinoamericana.
They're all freakin' over town, you pretty much have to swat them away like, well like bugs...these are the notorious beetle taxis though, the ones every guide and book and guidebook warns you away from. We didn't see any murders or robberies (involving these cabs) actually taking place, but you never know. Is that how you want to be remembered? Is that how you want to be talked about on your local news? There are countless legit taxis on the Mexico City streets as well, use them.
Avoid taking taxis from the street. Better call the "Sitio" ones which are safer or take them from you hotel.
If you are in the south part of the city, I recommend you to call the Taxis' Sitio of Perisur. It is more expensive but for toursts is an excellent option!
All of the horror stories that you have heard about driving in Mexico City are essentially true. But if you want to get around quickly (and fairly cheaply) take the Green Cabs. Notice I didn't say "get around safely". They do give new meaning to the term "aggressive driving". Just make sure to get a price up front and close your eyes for the duration of the ride.
You should BE AWARE OF TAXIS! Here is a very good link explaining what to take into consideration when taking a taxi-ride!
I used taxis from hotels, more reliable than the green ones! Just go at the entrance of a 4-5 stars hotel and ask the doorboy to order you a hotel-taxi!
I use taxis in Mexico City. NOTE: The Mexican government had reported that the very familiar green and white taxis are being phased out. Taxis will be red and white in the future. I really hate to see this change!
I've posted notes about taxi safety under 'dangers'
The only time I got robbed by taxis was on the airport taxis that charge 205 pesos to get to the Zocalo. After that I took green taxis with no problems and the drivers were very nice and I felt no danger. They charge a fourth of what the "safe" taxis charge.
We never used one, but like everyone else, we'd heard that these little green taxis were a sure way to get yourself assaulted. Who knows the truth behind these claims - we weren't adventurous enough to try one out.
A far better option if you have a specific destination is to use a tourist taxi. They are no where near as cheap as the little green bugs, nor as plentiful, but you're certain to reach your destination without having been mugged.
"Safe is always relative" ie. there is no guarentee that you won't have bad luck with the best of precautions, but here are a few suggestions for the first time visitor with little or no Spanish:
1) Know where you want to go. If you do not speak Spanish having a hotel card might help. 2) Do not get overly intoxicated. 3) If you have gone into a restaurant or club and you do not feel the place was a ripoff dive, ask cashier/manager for a, "TAXI de confianza, por favor" (taxi day con-fee-on-sa.)(You could ask them to call you a taxi (ya-ma-may un taxi por fah-vor) My experience is that they will be eager to help. (I have stood inside a place with Mexican customers while we waited together for our taxi's.) 4) Fix the price if there is no meter or it doesn't work before you go. (You can ask the cashier/waiter/managager -- Quanto? (Kwan-toe?)and confirm with the driver that price. 5) Do not take a taxi with someone already inside other than the driver. 6) Try to take a glance at the taxi driver license card before you close the door. If the picture does not match the driver, I suggest that you get out.
7) If you are just on the street, in a plaza or airport you have several options -- just do not take the taxi of someone who comes up to you asking if you want one. The rule in this situation is to choose your own taxi. I will even take one of the VW bug taxis if I see that it has just dropped off passengers. (Other people advise against using them at all as they are the most commonly robbed.) 8)Usually there are many places where taxis are lined up. Look for a sitio sign for a little re-assurance. 9) If you need help look for a policeman or shop owner. (Taxi, seguro. (say-gu-row) por fah-vor.) You chose the policeman, he or she choses the taxi.
The odds are heavily in your favor even if you do not follow these suggestions. These are just suggestions to try to improve those odds even more. I have taken many a Mexico City taxi without ever having a problem.
The green VW beetles crawl ... ahem ... like beetles all over the city! They're a sight to behold. BUT, they're to be avoided apparently, as many are mafia run, and have been known to kidnap tourists and other such woeful things. But they are cool. The front passenger seat has been taken out, so the passenger can jump into the back. Neat. Oh, and they're really cheap. Anyhow, according to a local there some are ok to take (they can't all be bad, right). So keep an eye on the licence plates and the condition of the car. Avoid ones w/out plates -like the plague - and ones in bad condition.
Cheap and readily availabe a fleet of VW taxis cruise the streets of Mexico city. However be careful as kidnapping have been known to happen.