Shulchan Aruch Chapter 249
Laws of Being Tied Down on Friday (4 Paragraphs)
Note: REMA is in brackets [ ]
1. You may not travel on Friday more then a distance of three parsas  in order that you should be able to reach your home when it is still strongly day and able to prepare the needs of the meals of the Sabbath. The same applies whether you are going to the home of others or staying in your own home. This only applies when you are settled and able to prepare the needs of the Sabbath. But if you are in a place that it is impossible to prepare the needs of Shabbat there, or if you are not in a place that can be dwelled in safely, then it is permitted to travel many parsas. If you sent notice to others that you will go to them for the Sabbath then it is permitted to travel many parsas in all directions.
2. It is prohibited to prepare a meal on Friday that is not normal to prepare during the week even if it is for a wedding feast. The reason for this is to honor the Shabbat so that one should enter the Shabbat with an appetite to eat. The prohibition applies all day. [A meal that the proper time falls out on Erev Shabbat like a Brit Milah (circumcision) or Pid'yon Ha'ben (redemption of firstborn) is permitted, so it appears to me and such is the simple custom.] To eat and drink without a set meal and even with a meal that is normal on a weekday all day is permitted according to the letter of the law. However, it is a Mitzvah to refrain from eating a meal that is common to consume during the week from nine day hours  and beyond.
3. The custom of pious men is to fast the entire Erev Shabbat.
4. If one accepted upon oneself to fast on Erev Shabbat then one must fast until the stars come out  if the time was not stipulated at the inception of his acceptance "until the congregation completes their prayers". [Others say that the fast is over when he exits the Synagogue and may eat. Therefore a personal fast he does not need to complete (until the stars come out). It is preferred to stipulate this at the time of the fasts' acceptance. A public fast he must complete (until the stars come out) and such is the custom.] If it is a fast made because of a dream, he must complete it until the stars come out.
 Day hours: Take the amount of time from sunrise to sunset in minutes and divide this by 12. This equals the amount of minutes in a day hour.
 72 minutes after sunset
 A parsa is 2.4 to 2.88 miles.
Translated by Jay Dinovitser 11/2012