- Mesa Verde National Park, Mesa Verde, Montezuma County1 objects
- Messenbach, Upper Austria2 objects
- Mexico4 objects
- Missouri1 objects
- Mohave County, Arizona1 objects
- Mokelumne Canyon, Amador and Calaveras Counties, California1 objects
- Montana1 objects
- Mount Lola, Nevada County, California1 objects
- Mount Shasta, Siskiyou County, California5 objects
- Mount Vesuvius, Naples, Italy2 objects
- Mouth of Kanab Creek, Coconino County, Arizona1 objects
- Mouth of San Juan River, San Juan County, Utah1 objects
- Mt. Konocti, Lake County, California1 objects
- NV-Pe-27 (Medicine Rock), Pershing County, Nevada1 objects
- Naga-ed-Der, Upper Egypt1 objects
- Navajo County, Arizona1 objects
- Nevada1 objects
- New Haven, New Haven County, Connecticut1 objects
- New Mexico14 objects
- New York City, New York County, New York1 objects