Collection place
- Ma'ats, Big Lagoon, Humboldt County1 objects
- Mabtuh Sarqi, Northern Syria2 objects
- Mabuiag Island, Near Western Islands, Torres Strait Islands1 objects
- Macas, Ecuador7 objects
- Macau (Macao)1 objects
- Macedon (ancient kingdom)12 objects
- Macedonia and Thrace, Greece50 objects
- Machilipatnam, Andhra Pradesh, India1 objects
- Machiqurg, Venezuela5 objects
- Machondo, Angola1 objects
- Mackenzie River, Northwest Territories, Canada25 objects
- Mackey Ranch, Apache County, Arizona17 objects
- Mackie Mound, Linn County, Western Oregon62 objects
- Mackinaw City, Cheboygan County, Michigan1 objects
- Macon, Bibb County, Georgia1 objects
- Mad River near Korbel and Blue Lake, Humboldt County, California9 objects
- Mad River slough, Humboldt County, California87 objects
- Mad River, Humboldt County, California112 objects
- Madagascar8 objects
- Madain Salih, Saudi Arabia5 objects