The most people with last name
Mountcastle lives in:
| Roanoke, VA | 7 |
| Raleigh, NC | 6 |
| Charlotte, NC | 4 |
| St. Pete Beach, FL | 2 |
| Baltimore, MD | 2 |
| Cornelius, NC | 2 |
| High Point, NC | 2 |
| Knightdale, NC | 2 |
| Cleveland, OH | 2 |
| Louisville, OH | 2 |
| Bedford, TX | 2 |
| Alexandria, VA | 2 |
| Virginia Beach, VA | 2 |
| Milwaukee, WI | 2 |
| Clovis, CA | 1 |
| Naples, FL | 1 |
| Panama City Beach, FL | 1 |
| Atlanta, GA | 1 |
| Marietta, GA | 1 |
| Savannah, GA | 1 |
| Kailua, HI | 1 |
| Wichita, KS | 1 |
| Boston, MA | 1 |
| Maynard, MA | 1 |
| Brookeville, MD | 1 |
| Hampstead, MD | 1 |
| Smithsburg, MD | 1 |
| St. Paul, MN | 1 |
| Durham, NC | 1 |
| Wrightsville Beach, NC | 1 |
| Brook Park, OH | 1 |
| Brunswick, OH | 1 |
| Canton, OH | 1 |
| Norman, OK | 1 |
| Conway, SC | 1 |
| Chattanooga, TN | 1 |
| Nashville, TN | 1 |
| Azle, TX | 1 |
| Frisco, TX | 1 |
| Grand Prairie, TX | 1 |
| Fairfax, VA | 1 |
| Herndon, VA | 1 |
| Triangle, VA | 1 |
| Caledonia, WI | 1 |