When you fly to Potrero Chico, you will most likely fly into the city of Monterrey, Mexico. The airport is small but quite nice. There are places to eat and souvenirs to buy. You pick up your luggage, hand in your customs questionnaire (you push a button and a randomly selected green light means to go ahead, otherwise they may inspect your luggage) and get immediately bombarded by friendly yelling taxi services, vying for your business. When I went to Potrero in February of 2002, I had reserved a taxi ride from Rancho Cerro Gordo who had either left before I got out of the baggage claim area or never showed, so I needed to get a cab. I checked my Spanish phrase book for some key words, and went over there. They were so happy to see me. There were 3-4 taxi companies fighting for me. One of them spoke English. All I had to say was Potrero Chico, Rancho Cerro Gordo, and they knew where I wanted to go. I got a ride for approximately $35-40 US and the driver met me out front. Very friendly guy. Barely spoke any English, and I barely spoke any Spanish, but we managed to communicate, talk about where I was from, and only ran into some complications when he tried to explain to me that if I gave him $5 equivalent of pesos, he would go on the highway and save us 20 minutes of driving. I was nervous at first why he would want more money than what I paid, but with my phrase book and some attempts at getting his point across, I realized he had to pay toll for the highway. So I gave him the money, he paid the toll, and gave me the change. Very pleasant guy, dropped me right off at Rancho Cerro Gordo where I was very happy to see Ethan waiting for me to show me where everyone was camping and help me with my luggage.
When I went again in January of 2003, I had it pretty much figured out. I got my baggage, changed my money, went to the taxi stand, said "Potrero Chico", they nodded, gave me a ticket for the 400 peso cab ride (approx $40), cab waited for me outside, I asked to take the freeway and paid the toll (30 pesos to get on, 16 pesos to get off), and all was easy.
The city of Hidalgo was bigger than I was expecting, with many small cinder-block cement buildings, one story high, painted bright pastel colors. The centerpiece of the town was a huge cement factory, and cement trucks would be rumbling by everywhere we went.
Tuesdays were market day, and you can get all sorts of food from street vendors, as well as clothes, gifts, candy, tools, cosmetics, music CDs, junk... Just take the main road from Potrero Chico and you can't miss it - right off the road and before the town plaza. It is crowded and fun, people hawking their goods, giant pots with boiling meats in them (undetermined organ-looking meats), fresh corn on the cob covered in cream, salt and a red powder I assumed was some sort of chili powder (I got the corn, but was too wimpy to try the red powder since I can't tolerate spicy food). Prices are very cheap. You only need to know to say "Cuanto cuesta?" for "how much does this cost?" and know your numbers in Spanish so you can understand the reply.
If you are thinking of buying eggs, think about something safe to carry them in. Otherwise, you'll just get a bag with loose eggs in them. Note that the popular brand of white bread here is called "Bimbo". You can get a big loaf of "Bimbo Grande". Feel free to conjure up your own images with that name.
We got some cheap and excellent looking fresh vegetables to make our own burritos with, and cans of refried beans. Didn't see fresh tortillas for sale, we ended up going to a small grocery store for them. We were warned to stay away from vegetables like lettuce, which absorb lots whatever nasties and pesticides are in the local water and soil and can't be easily removed just by washing. We ate many tomatoes, cilantro, onions, peppers and garlic with no adverse side effects, except perhaps for producing some of our own gaseous rocket power to blast us up the climbs.
Potrero Chico is some sort of municipal park with a town pool for the residents in the summertime. There's a road that goes right into the canyon, so the locals like to drive in, sit under the pavillion in the shade, blast Mexican polka-sounding music, drink beer and watch the climbers. This usually started later in the afternoon, around 3pm. So be forewarned it might get hard to hear your climbing partner over the music in the afternoon. Many of the locals were friendly and tried to talk to us. Everyone who passes by waves and/or says hello. It's very warm and friendly. But beware, there are local kids who love to go through your packs and take what they please. For this reason, everyone climbs up to the first or second bolt and hangs their pack there when they climb.
Note that in 2002, there was a large flood which wiped out the road and bridges, and pulled the foundation out from the Potrero Chico pavillion (which is still standing, but quite crooked).