South Dakota is an accessible state for travelers with disabilities. Most attractions, hotels, and restaurants are equipped to handle wheelchairs and have set aside parking spaces and provide ramps. All of the federal parks and monuments have provided for some level of handicap access, including handicap trails.
Mount Rushmore [1] has a 27-page Braille guide to the Monument available upon request from the information desk, and many of the films about the monument are both captioned for the hearing impaired and narrated for the visually impaired. Note that some of the historic buildings in some communities may not be accessible. If you have any questions about accessibility, particularly with historic accommodations, be sure to call and ask.
A service called Relay South Dakota provides telephone accessibility to people who are deaf, hard-of-hearing, or speech disabled. Available 24 hours a day, 365 days a year, call 800/877-1113. Visit www.relaysouthdakota.com [2] for more information.
Links:
[1] http://www.moon.com/destinations/mt-rushmore-the-black-hills/mount-rushmore-and-the-central-hills/mount-rushmore-national-monument
[2] http://www.relaysouthdakota.com