Virginia Lee Burton

A modern classic that no child should miss. Since it was first published in 1939, Mike Mulligan and His Steam Shovel has delighted generations of children. Mike and his trusty steam shovel, Mary Anne, dig deep canals for boats to travel through, cut mountain passes for trains, and hollow out cellars for city skyscrapers — the very symbol of industrial America. But with progress come new machines, and soon the inseparable duo are out of work.

...

A country house is unhappy when the city, with all its buildings and traffic, grows up around her.

Maybelle loves to carry people up and down the hilly streets of San Francisco, until the City Fathers decide that she should be taken out of service in the name of progress.