First solo backpacking trip in the Yucatan

I travel a lot alone in Mexico (and the world) and have met many other women. The younger, prettier ones run into more trouble than us over-50 types. When you backpack, you'll run into other people, men and women, who may be interested in accompanying you to certain places. You can take combis and buses easily. Taxis are more iffy for a single woman. Guard your possessions and be aware of your own emotional reactions to people. Always. If you feel uncomfortable, vulnerable, or that an area is not safe for any reason at all (Dont' think about it, don't talk yourself out of the feelings) just get out of there as quickly as you can. Dont' worry about hurting someone's feelings, slapping a man's hand away or anything else. They have more respect for a woman who stands up for herself. If you feel creeped out by anyone on a bus, move up to the front where the driver is, or sit next to an older person. Travel as often as possible with others, talk to people, learn some Spanish (a lot if you can) and practice with hotel clerks, vendors in the markets, get easy with the language. This will help more than anything else. Make sure you lock doors, keep stuff locked up in the hostels with a good lock, and simply stay aware. If you drink, stay sober, don't drink too much. Doing drugs means you'll be in contact with cartel types and that is the worst idea in Mexico, hands down. Learn some basic self defense and practice it till you feel comfortable screaming, hitting, punching, and aren't afraid. When you are not afraid, it shows on your body and people who might want to take advantage will pick someone else. All that said,you will have the time of your life. You will make mistakes and be scared sometimes, but you will also experience some of the warmest people in the world, great food and scenery, and be impressed by ruins dating far back in time. Best of luck to you and keep your folks in the loop daily or at least every other day, so they know where you are and what your plans are. This is great insurance. If you dont' check in, I suspect they'll come looking for you! BTW, if you have a Verizon phone, you can get Mexico Talk and Text, and be in cell phone contact all the time with people back home. That ought to make your parents feel better about the whole trip.

You're travelling along the gringo trail - lots of tourists and the cities you're going to are well set up for them. I wouldn't worry about traveling alone. Just do your traveling during the day and the rest is common sense like not getting drunk in local bars and being aware of your surroundings. Your hotel or hostel can put you in touch for trips or tours to Mayan ruins, cenotes, markets and other places of interest.

But here are a couple of travel blogs operated by world traveling, young, single women. I am a travel blogger as well and from my experience theseI are two of the better travel blogs by single women - we have them linked on our blogroll. They have lots of good advice (for everyone as well as women traveling alone). adventurouskate.com and nomadicchica.com

Brittany, you'll be fine and will have a great time. It is a well traveled gringo trail your on, you'll meet ton's of other travelers your age, easy. You can team up to split costs and will feel safer but again no worries, just follow the basic precautions.

Is it safe to take taxis and colectivos by myself to ruins and cenotes?

Yes, if you feel the need ask the hostel/motel to call for a driver, they are a good source of information. By day 2, heck by the evening you'll have met several new friends in the same situation and be laughing at what the big deal is, the Yucatan is very safe and friendly.
Oh yeah, don't plan on being in contact all the time with folks back at home, you'll be having too much of a good time.

I notice that ADO, the dominant intercity bus carrier in south and south central Mexico, is now advertising an extra cost option (14 MXN or so) for woman travellers to be seated beside another woman. But the last place, in my opinion, youll run into trouble would be an intercity bus. More likely someones hand will wander while youre crowded into a combi or colectivo taxi; be careful where you seat, and if youre not comfortable, wait for the next ride.

I sent you a private message.

Another note from me on buses. Most of the intercity buses are not packed and although they assign you a seat, you are free to sit anywhere you like if there are open seats. The next stop somebody might have your seat assigned to them, but you can always move to some other seat. As others have pointed out, it is a gringo trail. You'll be fine. It'll be the trip of a lifetime, until the next big trip takes its place.

You should not have any problems. I have been traveling around this area of Mexico since l990. Some times alone and some times with others. Do not carry a purse or wear anything that would attract a thief. Like watches or expensive sun glasses. Don't wander around drunk after dark alone. Do not display too much flesh . all should be fine. Photos on wolf calls.com

For the record, municipal police in Yucatan state don't even carry guns (state and fed police do). Violent crime in the area is so minimal that guns are seen as unnecessary, and as a rule the farther you get from the big tourist hubs like Cancun and Playa the safer you'll be. I have friends (attractive 20-something women) who run alone on the country roads in Yucatan state every evening during the summer. Granted they speak Spanish and people in the communities know them so I'm not suggesting you do the same, but it should be some illustration of how little you have to worry about.

In general, a woman traveling alone in this part of Mexico faces no particular security concerns that she wouldn't face as a solo traveler in the US, with the only exception being the disorientation that not speaking Spanish can sometimes lead to. Pick up some Spanish, keep your wits about you, don't get hammered with strangers, steer clear of any and all drugs, and you'll be fine.

To one of your specific questions:

Is it safe to take taxis and colectivos by myself to ruins and cenotes?

Yes, absolutely. I recommend renting a bike to visit cenotes near Valladolid.