|Location Map ( geo)|
|Distance:||53 km (32.9 miles)|
|Meets:||M1, R168, N2, R163, R162, R147, R895, M3, R164, R154, N52|
The N51 runs from junction 10 of the M1 at Mell, west of Drogheda in County Louth to the N52 at Delvin in County Westmeath by way of Slade, Navan, and Athboy in County Meath. It intersects the M3 at Junction 9 west of Navan.