Stairs.

Technology  To China and a selection of photos of a new invention best explained by the first caption:

"Liu Tie'erlooks at a wheelchair he invented in a workshop in Guangzhou, capital of south China's Guangdong Province, May 6, 2013. Liu Tie'er, a 71-year-old local resident, invented a wheelchair capable of climbing stairs in an effort to help his disabled wife and many more who are in need."

There are a variety of designs to suit every occasion.