Issues for women traveling in the U.K.

Be smart. Don't leave your bag on the bar; many pubs have purse hooks (just be sure you keep it between your knees as you sit, and take it with you when you use the loo)

What women can expect on vacation in the U.K.

European travel is as easy for women as it is for men. You may get complimented, whistled at, pinched, prodded, or propositioned, but you’re probably physically safer there than you are at home. (Europeans see rape as even more repugnant than Americans do, and there are fewer reported rapes in Europe.)

Some feel more comfortable joining a tour—either a general tour group, or a women-only tour.

Women’s lib notwithstanding, women seen without men are targeted more often by thieves, so be extra careful.

You won't run into this as much in the U.K., but if you travel elsewhere in Europe know that many European males, especially those in Southern European countries, act like peacocks around women, parading around to win admiration. When this behavior is not overly annoying, it can be quite comical.

A single woman, or a group made up solely of women, will get approached far more often than a man or mixed group. Look on the bright side.

This can be a great opportunity to make friends, get instant language lessons, or flirt. It can also be a darn nuisance.

Just pick when you feel it’s safe and you’re in the mood to be friendly, and when you should firmly ignore all those men falling over one another to be helpful, charming, and gallant.

Tips

Dress modestly to avoid unwanted attention, and wear dark shades to avoid eye contact (direct eye contact seems to translate as "come molest me” in some countries).
The farther south in Europe you move, the more ardent your suitors will become. In fact, the inverse is sometimes true—British men can be difficult to approach even if you want to.
Always be married... even when you're not. Guys are less likely to hassle a married woman. One trick that has worked wonders for solo women on the road is the fictional husband (and he works even if you’ve got a spare one at home who happens to be real). This faux hubby is always just around the corner where you’re going to meet him in five minutes, he's built like the Terminator, is definitely the jealous type, and best of all, he always leaves the toilet seat down. Even if you haven’t actually tied the knot, you might want to wear a fake wedding band to ward off the more assiduous admirers.
One step up from the fake husband: Puff out your belly and keep absently patting it in the universal "I'm pregnant" manner.
Take your hint from local women and stride confidently and purposefully down the street, those sunglasses firmly in place. (Imagining you're Audrey Hepburn helps.)
Ignore any comments, catcalls, and wolf whistles, refuse to engage the harassers in so much as eye contact, and firmly fend off all courtiers.
On trains, sit with other women or families. Avoid empty train compartments, because then your companions can choose you instead of the other way around. Instead, find a couchette with five nuns and one empty seat and ask if you can join them.
If you find yourself molested on a city bus or other crowded place, tell the transgressor firmly “No!” and “Alt!” (international-ese for “stop”) and proceed to pinch, scratch, elbow, kick, punch, and so forth to further discourage him. Also, enlist the aid of a nearby local woman to noisily chastise the offending would-be Romeo and perhaps whap him with her purse.

All women should take precautions and play it safe, but even solo women should have few problems traveling alone, although it certainly helps and is safer to have a companion (of either gender).

Why you're suddenly such an easy mark

Unfortunately, Hollywood films have provided Europeans with the impression that all American women are easy —blondes doubly so.

In many ways, Europe remains a rigid, formal, “traditional” society. The fact that American women are used to being more independent, straightforward, and openly friendly than their European counterparts has the unfortunate side effect of reinforcing that Hollywood sexpot image, where every American engages in a sex scene at least by the end of the second act.

The practical upshot: American women are seen as fair and likely game.

Now that all of that has been said: You should feel relatively safe, even in big cities, even at night. Many women report feeling much safer in European cities than they ever do at home, and they even feel fine walking through the deserted streets in the middle of the night all alone (not that I am recommending that).

Of course, it always pays to play it safe. Stick to populated streets after dark, and know where the bad neighborhoods are. The bottom line, sad as it may be, is that physically you have much less to worry about in Europe than you do in most parts of the United States.

Women's travel resources links