When traveling internationally you will need to obtain a few additional travel documents. This includes those traveling to the Republic of Ireland. Ireland is on the north west coast of the United Kingdom, and like a majority of the world, was once under British rule. Make sure you have all of the required travel requirements, otherwise you may not be allowed to enter the country.
As it is with all other foreign countries, you will need your passport to gain entrance to Ireland. Visitors from the United Kingdom are not required to carry a passport, however you do need to prove you are from the UK, so carrying some sort of state issued identification will be necessary. You can apply for a passport (if you do not have one) at your local post office. For your passport photograph it will be best to have a professional passport photographer take your picture, due to all the strict requirements. After applying for your passport you will receive it in a few weeks.
Most European nationals, as well as individuals from the U.S., Canada, New Zealand and Australia do not need a Visa. All other citizens of foreign countries will be required to apply for a visa.
Luckily, for those who hate needles and shots of all kinds, there are no vaccinations required for admittance into the country. As long as you are healthy you can come as you are. However, when traveling by plane from the United States make sure to have all your medication in opened medicine containers in a sealed bag. Additionally you will need all liquids of any kind in three ounce or less containers and placed into a one gallon sized bag.
You can't go anywhere, much less through airport security, without a boarding pass. Once you depart on your plane you will not need your boarding pass. With this being said you will most likely need proof of your return flight. This can just be an email print off from your online booking reservation or your actual return ticket. Without the proof you will most likely still be let into the country, but it can cause a few minor delays at customs.