My latest trip was to the area around Puerto Vallarta, Mexico. It is clearly developing and becoming home to both retirees and snow-birds. They even have a Costco, a Home Depot and a WalMart. I was curious to see what was for sale in them, but I didn't want to spend my vacation doing that. Instead we took a bus to Guadalajara, a beautiful city that still has its colonial structures in the center despite having grown to 12 million! 
My favorite part of town was a section called Tlaquepaque, which used to be a distinct town but has been engulfed by the growing city. I find it interesting that the word Guadalajara comes from Arabic and the word Tlaquepaque is from Nahuatl (the language of the Azteca). This is what you find all over Mexico - words from Arabic into Spanish and words from the indigenous languages. As a linguist, I find it fascinating.