The 1878 Jackson's Sawmill Covered Bridge or Eichelberger's Covered Bridge is a covered bridge that spans the West Branch of the Octoraro Creek in Lancaster County, Pennsylvania. 

A county-owned and maintained bridge, its official designation is the West Octoraro #1 Bridge. The bridge is purportedly the only covered bridge in the county that is not built perpendicular to the stream it crosses due to the placement of the sawmill on one side of the bridge and the rock formations faced by the builders on the other side.

The bridge has a single-span, wooden, double Burr arch trusses design with the addition of steel hanger rods. The deck is made from oak planks.  It is painted red, the traditional color of Lancaster County Covered Bridges, on both the inside and outside. Both approaches to the bridge are painted in the traditional white color.

In 1980 it was added to the National Register of Historic Places as structure number 80003520, but it was removed from the Register in 1986.  Due to its remote location in an isolated part of the county, it is seen less than many of the county's other covered bridges that are closer to the major population centers such as Lancaster.

The bridge was built in 1878 by John Smith and Samuel Stauffer at a cost of $2,410. In 1985 it was washed mostly intact from its foundations and deposited a short distance downstream in a flood. It was repaired and reset at a cost to the county of $75,000. During the rebuilding, the bridge was raised 3 feet to protect it against future flooding.  The bridge underwent a recent rehabilitation in May 2005.

Length of largest span: 139.1 ft.
Total length: 149.9 ft.
Deck width: 13.8 ft.
Overhead clearance: 11 feet 6 inches
Under-clearance: 14 feet 

Located at:  N39 53.807    W76 04.809     -     WGCB #38-36-33

Photographed in September of 2008.