If you are meeting someone at a pub, don t be afraid to go in on your own. You are much safer in the pub, under the protection of the publican or bar staff, than you are hanging around on street corners. If the pub is full of males who all look up when you come in, don t take it personally. It usually just means that this is a local pub, where people know each other and automatically look up to see who is coming in. An unfamiliar face will, naturally, attract some attention, and perhaps some curiosity, but they will eventually lose interest.
Some pubs are more female-friendly than others.
If you want to be left alone, it is generally best to sit at a table, rather than at the bar counter, as this will signal a desire for privacy. But if you are worried, choose a table reasonably near to the bar, so that you are constantly under the protective eye of the bar staff. If the bar is not busy, you may choose to stay at the bar counter, talking to the publican or bar staff. If you feel a bit exposed when the pub gets more crowded and the bar staff are busy serving other customers, you can always move to a table. So, if you feel at all uncomfortable with someone, do not accept the offer.