The key to Tres Dias is the Weekend. It is three days (Tres Dias) starting on a Thursday evening and ending on Sunday evening. Real 24 hour days. The attendees are sequestered to screen out the distractions of everyday life. Nothing to worry about. No meals to fix, no phones to answer, just great fellowship, discussion, praying, sharing and lots of fun.
You will have fun!
Anyone who thinks real Christians are stuffy and boring is seriously mistaken. After all, God gave us our sense of humor. So we sing, and laugh and study (but it's fun, not boring) and generally have a great time.
Weekends can only happen once in a lifetime. Most people find them transforming, and often refer to the weekend as a "mountain top" experience. You will meet some really great people, and hopefully make some new life-long friends.
There are two men's weekends and two women's weekends each year, one each in the Spring and Fall. If your schedule doesn't permit you to attend the one coming next, then put the one after that on your calendar so that you keep the date open.