Andy over at The Sims Zone has started his in-depth review of The Sims 3 World Adventures. Part 1’s segment involves the mechanics behind traveling and proper visa management.
Once a sim starts to go on a world adventure, they begin with a Level 0 visa in each of the three countries. Without any other extensions, it means that the default length of time that they can stay is 3 days.
From experience, I have found that three days is not enough in most cases. Three days is NOT enough in most cases. To be in sight of the relic you have been searching for, only to find you are on the way back home is incredibly irritating.
In order to improve the level of visa and the length of their stay, they have to accumulate enough visa points. Visa points are gained from completing many of the adventuring opportunities that come their way while they are abroad.