Thanks so much for bringing up this very important discussion topic. I see it as an exciting opportunity for us! In the words of @Ken Graham:
This not only will make many individuals happier in the Great Outdoors, it will expand the awesomeness of this site and communicating that we are thinking of others.
I see @imsodin's point about avoiding adding tags before we really need them. On the other hand, I love tags and use them frequently. I even searched for an accessibility-type tag when the bike-wheelchair question came up, but didn't find one. Then I did a text search in the Q&A box and found the word "accessible" in 98 posts, and "access" in 252. They're used in a number of situations so it supports what seems to be the decision not to rely on it.
However, that might actually be a good reason to add a more specific tag.
I don't know what to name it, and think a lot of things would work. My various issues come from a number of different circumstances. I have an inner ear disease so I've lost almost all of my hearing. The same disease causes vertigo and other problems with balance. The rest are mostly from accidents and another disease. I fall into categories including "disabled", "challenged", "handicapped", "limited", "injured", "impaired", "ill", "compromised". Please don't see this as an invitation to feel sorry for me. In fact, I don't like that. I'm just saying that I don't mind these labels. People with mental or psychological impairments, or other diseases that carry more stigma might be more sensitive to the wording.
If everyone likes disability-options, I'm fine with that! Whatever name we end up with, I'd like to suggest using "impairments" in the description. Also, what if we kept the "wiki" more general, and then got more specific in the longer "information" section?
@Charlie Brumbaugh, what do you think of using this for the "wiki" part:
Questions about improving the access to or enjoyment of the Outdoors for people with disabilities, impairments, limitations or special needs of any kind.
For some people like me, in order to enjoy life to the fullest, and especially outdoors, accommodations and adjustments have to be made, so maybe those might be good words to use somewhere in the longer description. Some tag descriptions point to questions that have been used as examples, so we could use the two you referred to in this question.
I have a few ideas for questions that could use these tags. @niall, I'm not saying they wouldn't be fine with our generic tags, but I think they'd be better with something more specific.
Does the (State Park, historic location, etc.) provide wheelchairs or walkers for those of us who only sometimes need them? (Yes, many places keep wheelchairs, etc. for just that purpose.)
Which stops along the road up Cadillac Mountain in Maine have handicapped bathrooms?
Is there a wildlife sanctuary in Massachusetts that caters to visually-impaired people? (The answer is yes. Audubon has a sanctuary that has a wheel-chair accessible trail that also has ropes to hold onto and signs that have braille.)
What are the laws in (geographic location, park, cruise, hotel, camping trail, etc.) regarding bringing a service dog?
Do any of the restaurants mentioned in (choose an existing question with a location someone has visited) have a gluten-free menu? (This question was a direct result of @Ken Graham's comment on Charlie Brumbaugh's answer. I'm glad he mentioned it because I have a daughter-in-law and granddaughter who both have celiac disease and peanut allergies. They do a lot of traveling, and have to be very careful where they eat. Many travelers are similarly affected, so it's an important consideration.)
Maybe other people could add some example questions regarding different types of special needs.
Thanks again to all of you!