Folkestone Harbour Arm - “Reaching into the English Channel, offering views of the White Cliffs and glimpses of France, the Harbour Arm is a unique cultural attraction; a place to meet friends, see live music and sample the goods from over 70 independent food, drink and retail vendors” - "Folkestone Harbour is a historic site; however, the majority of Folkestone Harbour is accessible by all users. Ramps and slopes have been installed to allow access to a vast majority of the sight. Where there is not direct access, alternative accessible routes are available for users in wheelchairs and mobility scooters.
The boardwalk is not recommended for use with wheelchair or mobility scooter. Folkestone Harbour maintain an accessible route between Fountain Square and Folkestone Harbour. Most restaurants and bars with internal seating spaces are accessible by ramp at the entrance to the business where necessary, please check with individual businesses about their provisions."
folkestoneharbourarm.co.uk/information/
Historic Dockyard - Chatham - 80 acre site, over 100 historic buildings and structures, three historic warships, Victorian Ropery Tour, RNLI Historic Lifeboat Collection - "Galleries and attractions are generally accessible to all visitors but for full accessibility details please see our Access Guide – available as a PDF" download here
as of Sept 19 it also has a Changing Places facility 
thedockyard.co.uk
Hop Farm Family Park - attractions and exhibitions to entertain the kids and fuel their imagination, indoor and outdoor, for families with children under 11 years old - Disabled & Pushchair friendly see website
www.thehopfarm.co.uk
Kent & East Sussex Railway - rural light railway runs from Tenterden for ten and a half miles of the Rother Valley, to terminate in the shadow of the magnificent National Trust castle at Bodiam - "There are parking spaces for Blue Badge holders near to the platforms at Tenterden Town and Northiam Stations and accessible toilets at Tenterden, Northiam and Bodiam. We are proud to boast a specially designed coach called Petros, which is fitted with ramped wheelchair access, wide aisles, moveable seating and an accessible toilet. . . Some of our other carriages have ramped access too and there is full wheelchair access to the shop and Station Refreshment Rooms at Tenterden Town Station. The Colonel Stephens Railway Museum has level access with 42" aisles. The Tenterden ticket office is fitted with an induction loop"
www.kesr.org.uk
Kent Life - 28 acres of fun from hands-on activities for kids to age-old farming traditions, animals to cuddle, tractors to ride, play areas to go wild in, fascinating historic buildings to explore - Disabled & Pushchair friendly / baby changing - some wheelchair restrictions please see website
www.kentlife.org.uk
Powell-Cotton Museum & Quex House and Gardens - Museum of African and Asian wildlife and ethnography collections, House, informal gardens, indoor and outdoor play area, Secret Garden Centre, Craft Village - The Museum, ground floor of Quex House and the Gardens are all accessible for wheelchair users
ww.quexpark.co.uk
Romney Hythe and Dymchurch Railway - best known for its superb fleet of one-third full size steam trains and diesel locomotives, all of which have been built to run safely at speeds of 25mph on rails only 15 inches apart. All of the steam locomotives were built between 1925 and 1937 - Disabled friendly / facilities please see website
www.rhdr.org.uk
Royal Engineers Museum - Museum Library and Archive, armoured vehicles, a Harrier Jump Jet and even a V2! To rare silks from China, exquisite jewellery made by Zulu warriors and a superb photographic collection - Prince Arthur Road, Gillingham - Disabled access / facilities / babychanging please see website
www.re-museum.co.uk/visiting
Spa Valley Railway - Steam and heritage diesel trains between Eridge, Groombridge, High Rocks and Tunbridge Wells - Most areas can be accessed from the level or by wheelchair-friendly ramps "the majority of our trains are equipped with ramps to permit ease of access for visitors with reduced mobility"
www.spavalleyrailway.co.uk
Spitfire & Hurricane Memorial Museum - original examples of the two World War 2 fighter aircraft - Manston - we have no info of disabled access -
www.spitfiremuseum.org.uk
Turner Contemporary - making art open, relevant and fulfilling for all,temporary exhibitions, events and learning opportunities - Fully accessible for visitors, with a ramp to the main entrance and café, as well as an internal lift to all upper floor galleries
www.turnercontemporary.org