| The Haven, Boston | |
|---|---|
 The Grand Sluice where the River Witham empties into The Haven. The lock is on the far right. | |
 | |
| Location | |
| Country | England |
| Physical characteristics | |
| Source | |
| • location | Grand Sluice, Boston |
| • coordinates | 52°58′52″N 0°01′45″W / 52.9811°N 0.0292°W |
| Mouth | |
• location | The Wash at Black Buoy Sand |
• coordinates | 52°56′01″N 0°04′51″E / 52.9336°N 0.0808°E |
| Length | 4.3 miles (6.9 km) |
| Basin features | |
| Tributaries | |
| • left | Maud Foster Drain, Hobhole Drain |
| • right | South Forty-Foot Drain |
The Haven is the tidal river of the port of Boston, Lincolnshire in England. It provides access for shipping between Boston Deeps in The Wash and the town, particularly, the dock. It also serves as the outfall into the sea of the River Witham and of several major land drains of the northern Fens of eastern England, which are known collectively as the Witham Navigable Drains.