If you're having your wedding ceremony in a church, chances are you've booked another venue for the reception. Or maybe you're getting married outdoors and taking the reception indoors at a party space that's miles away. That's great, but it's also less convenient for guests than a one-venue wedding would be. Think about the following to minimize the inconvenience for your family and friends.
The lag time between the ceremony's end and the reception's start should be kept to a minimum.
Assuming the two venues are close to one another, there should be no more than two hours separating the ceremony and reception. So, assuming your ceremony is under a half hour, if your nuptials starts at 3:00 p.m., and it takes 15 minutes to reach the reception venue, your party should start by 5:00 p.m. If there's more of a lag than that, anyone who's not local will have to figure out how to kill hours of dead time in a town they're not familiar with.
Consider whether the extra traveling will be problematic for older guests.
It may be difficult enough for some elderly guests or anyone with mobility issues to get from Point A (home) to Point B (ceremony venue). If you add getting from Point B to Point C (reception venue), you may be getting several "can't-attend" RSVPs from important people in your life.
Sending a reception card with relevant info is courteous.
If you can't avoid a long gap, when you send out the wedding invitations, include a reception card to give guests a heads up. Give them some ideas of how to spend those three-plus hours before the reception starts, such as where to get a cocktail or which local museum to pop into. Post the information on your wedding website and in welcome bags, too. If any friends or family are willing to host a prewedding get-together in their nearby home, take them up on the offer and pass the information on to guests.