Awesome experiences are best shared. Whether a spouse, love interest, friend or family, sharing the experience with someone is awesome. Breakfast, dinner, post ride time all create great memories. Better if your guest can ride with you, but if they are not a rider, better they do not!
If your guest is NOT a registered rider, they may NOT follow you along the route in any way, shape or form. Guests are prohibited from driving any of the segment from the day's launch to the day's destination at any time that day until the last rider has checked in at the destination. If your guest chooses to violate this, whether by mistake, getting lost or intentionally, you and your guest will be ejected from the ride with zero refund. First time, no warnings. The park service was quite adament on this point, and from a safety standpont we are in 100% agreement.
Aside from that, your guest can drive yesterday's segment or tomorrow's segment all they would like. There are plenty of great destinations on the Parkway and near the Parkway that someone with a day to spare and a car can really enjoy.
After the morning rider launch, guests can obtain touring advice based on the sort of things they are interested in seeing and doing. The area is rich in cultural and regional resources that people will find quite enjoyable and within easy driving distance of the launch and destination.
An Awesome Week on a Bicycle!