Puerta Vallarta or Puerto Vallarta?

As I've been researching Vallarta (as this lovely city is often called) for this website, I've noticed that many times people write its name as Puerta Vallarta. If you know a little Spanish, this is a reasonable guess, since adjectives take the gender of the nouns they are describing... "red table" is mesa roja, for example.

But in Spanish, this city is correctly called Puerto Vallarta. Puerto means port, and puerta means door. This began as a port town. The town was known as Las Peñas until 1918, when it was renamed in memory of a lawyer and former Governor of the state of Jalisco, Don Ignacio L. Vallarta.

So do call it Puerto Vallarta instead of Puerta Vallarta! Easier yet, just call it Vallarta and you'll sound like you live there! And since so many people do spell it Puerta Vallarta in the search engines, I'm including a few links here with the -a spelling:

Ahem... I'm about to post several pages I've just written on this city, and as I ran the spell-checker, I discovered that I've spelled it Puerta Vallarta by mistake more than once!