Talk:San Miguel de Allende
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I've traveled to San Miguel many, many times now, More often than not, I try to find a way to circumvent the bus system with some combination of planes and taxis. And more often than not, I find the planes and taxi process distasteful, and I wonder why I don't just take the bus to and from everything.
Let's be clear: if you've ever taken a Greyhound bus in the States, the bus networks throughout Mexico are NOT like that. Nor are they the chicken-coup jalopies many people envision when they think of a bus in Mexico. The lack of major airports throughout Mexico has profoundly affected the bus system here - there are dozens of private buslines, all highly-competitive, and the result is that most buses provide the accomodations you'd expect from business class airlines. Spacious, reclining seats, box lunches, potable water and coffee, clean bathrooms, and movies (usually in English or English-subtitled) are standard fare for most buses, and the price is about half or a quarter of what you'd expect from Greyhound.
Queretaro in particular has one of the largest bus hubs in Mexico, so flying into Queretaro will ensure you a quick bus to San Miguel (or anywhere in the region, for that matter). As of this writing, there is no direct bus route from Leon to San Miguel, but there are inexpensive shuttle services (around $30 American). Note that there are TWO bus depots in Mexico City: the Airport depot and the North depot. 
You may also want to consider taking a bus from a much more distant starting point, like Cancun or a border town. I've done this several times, with varying degrees of enjoyment. (Bring a book - hours upon hours on one bus can wear you down.) I'd recommend against this journey if you're not a seasoned traveler or otherwise adventurous - such a trip will take you through portions of Mexico that haven't been carefully sanitized for Western sensibilities. I was once on a bus from Cancun to Queretaro that stopped for lunch at a hole-in-the-wall restaurant - chickens were literally roaming free around the tables while we ate their brothers and sisters. The good news: beside giving you a chance to see more of Mexico, a long bus ride can save you a tremendous amount of money. Especially during the Holidays, a plane to Houston and a bus from Houston to San Miguel can cost you a third the price of the same plane ticket going to Mexico City. 
Yes, there are downsides. First of all, like a regular bus, frequent stops are the norm. A short hop trip, like a bus between Queretaro and San Miguel, may have zero or one stop, while a bus from Monterrey may have a half-dozen. Second, despite the competitive industry, you will occasionally find a bus that does something obnoxious like drive away without you. (I've had this happen only once to me.) And of course, there's the tragedy of having to "slum it" with the locals. But all in all, if you can get over yourself and your fear of buses, I think you'll find the bus system in Mexico infinitely more appealing than any other form of transportation. [http://www.visit-sanmiguel.com
]Regarding the bus from Leon to San Miguel de Allende, yes, there is bus service! It's more of a local type bus, since the distance is so short, with none of the amenities you'd find on a first class or executive class bus.
On other thing worth mentioning is the large number of retirees. It was mentioned twice in the article but it bears mentioning again. The place is crawling with them! They've done their best (or worst, depending on your point of view) to Americanize SMdA, and I think the town has suffered because of it. I don't mean to scare anyone off, but be aware of what you're going to encounter. And the silver lining for those of you who don't speak Spanish is that many many people speak English. (Also, for this reason, I wouldn't pick SMdA as a place I'd go to learn Spanish.)
To counterbalance my warning of all the old American people, there is also a cool younger scene if you can find it. There's at least one "secret" club for the hipsters and fresas, if that's your scene.
San Miguel de Allende is certainly worth the visit.