All three museums charge an entry fee, but this Wherigo tour does not require one to enter any of the museums. Each of the museums is housed in an interesting building. More than one stop do not even require you to leave your cache mobile.
I believe the entirety of the Wherigo to be friendly for those with disabilities, but I would rather err on the side of caution.
This cartridge was tested on an Oregon, a Nuvi 500, and with the iPhone app, and all worked perfectly. Maybe that is the beauty of simplicity.