This week marks 75 years since the first McDonald’s restaurant opened for business -- and what a strange, strange trip it has been.

While the fast-food chain is the largest in the world, the company has been in a serious slump in the last few years. Earlier in May, the company announced a turnaround plan after more than a year without a month of same-store sales growth in the U.S.

Entrepreneur

Starting delivery service in New York City.

Entrepreneur

We must admit, ordering McDonald’s to the Entrepreneur office earlier in May went better than expected.

Serving breakfast all day.

Lucas Richarz | Flickr

Crafting lentil and eggplant salads.

The Corner | Facebook

Opening up in churches.

ventanamedia | Foap.com

Okay, McDonald's never actually did this but a Christian design consultancy launched an Indiegogo campaign based on the idea.

Hiring a Mythbuster to talk about pink slime.

McDonald's | YouTube

Trademarking McBrunch.

ilaria | Flickr

Introducing a terrifying new mascot.

McDonald's

Giving Ronald McDonald a makeover.

McDonald's

The mascot debuted his new look when he joined Twitter last April.