Rancheradeb and my family live in Chihuahua, Mexico. So we try to visit them as often as we can.
Where do you plan on traveling to? That will be important to know, since all states in Mexico are different. Mexico has actually implemented a program that promotes safe driving on the road. So depending on where you are headed to, you will pass thru several toll booths. So make sure to have change, usually its about 2-3 US dollars.
Make sure to take you license, birth certificate or US passport. When you cross the border you will need to acquire a permit for your vechicle. Also if you plan on staying in Mexico for two days, you and your family will need to get a tourist card.
lines might get a wee longer, as local govts are implementing new rules (i.e. need proof of citizenship when re-entering the US). it varies from state to state, though.
We drive to Mexico several times a year. As long as you bring your proof of citizenship and don't break any rules (i.e. transporting produce, etc), it's fine.
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"We live in an age where unnecessary things are our only necessities." --Oscar Wilde
We drive to Mexico often too, and maybe it depends on the boader crossing, but the one we go through is an absolute NIGHTMARE on the return at peak times. After experiencing 4 hour waits and hearing other horror stories from friends, we always plan our trips to come back on a Monday or Tuesday (never Sunday). Getting in to Mexico is always a breeze.
Definitely remember your passport, because the requirements have offically changed for land crossings. I can't think of any cultural things to point out, except to expect some poverty. The things I dislike the most are street vendors and time share hawkers.
I forget to mention that US car insurance is invalid in Mexico - be sure to get Mexican insurance. It's really easy, we get it through Geico.
Does anyone have suggestions where to go? I really have no clue. All I know is i'll be entering through El Paso, TX and I probably won't want to go more than 3 or 4 hrs South of the border.
I would love to see anything ancient and local crafts.
Also, can I use American money or should I get it converted before I go? Or do I just find an ATM once i'm in Mexico?
The currency depends on where you are going. My family goes to Rocky Point, and it seems they actually prefer US currency, but as you get farther from the border, I would guess that is subject to change.