Ira, you are right on the mark with the solid walkways! Not only old folks, but those with disabilities can find gravel walkways impossible to negotiate. As one who has spent a lot of time in a wheelchair, and now with a cane. I can tell you that gravel is a barrier that you can't beat. Even uneven surfaces make wheelchair travel almost impossible. I wonder, does the museum come under the Americans With Disabilities Act? If so, then handicapped accessible restrooms will be required, and it doesn't make much sense if the handicapped folks can't reach the rest room because of a dirt or gravel sidewalk.
Keith