| Sylvanus Marriage Octagonal Barn | |
| Coordinates: | 47.6139°N -99.0972°W |
| Built: | 1902 |
| Architecture: | Octagonal barn |
| Added: | October 7, 1986 |
| Area: | less than one acre |
| Refnum: | 86002748 |
The Sylvanus Marriage Octagonal Barn near New Rockford, North Dakota, United States, was built in 1902. It meets the current, practical definition for a round barn. It was listed on the National Register of Historic Places in 1986.[1]