There are 2 common questions that come up during vacation season. First, is the Sunday obligation waived if we are away from our home parish? And second, are there circumstances that can lessen our culpability if we miss Mass? The Sunday obligation is one of the Precepts of the Church, duties that the Catholic Church requires of all the faithful. These aren't mere guidelines, but rather a list of things that the Church teaches are necessary for Christians to do in order to advance in the Christian life. For that reason, they are binding under pain of mortal sin, so it's important not to disregard them for anything less than serious reasons.
The Catechism of the Catholic Church states that the first precept is "You shall attend Mass on Sundays and Holy Days of Obligation and rest from serville labor." You'll notice that the statement isn't qualified; it does not say, "When you are at home" or "When you're no more than X miles away from your home parish." Our obligation is binding on every Sunday and Holy Day of Obligation, no matter where we are.

In our high tech society, it is easy to find masses anywhere you might be going. All smart phones have free mass apps that tell you addresses and mass times for churches by several criteria, so download an app so you are prepared. If you don't have a smart phone, do your homework before you go. If your trip is in the middle of nowhere, talk to Father before you go and ask for dispensation. May the Lord go with you on your travels and provide safe passage and plenty of rest and relaxation.