Allendale Quadrangle Traditional Cache

The cache is placed in the USGS Allendale Quadrangle in California. It is the 36th in our series of caches placed near the site for which a USGS 7½-minute quadrangle map is named.

Allendale is a populated place, Class Code U5*, located in Solano County California. It is located along I-505.

The Quadrangle boundaries are:
N 38º 22’ 30” and N 38º 30’ 00”
W 121º 52’ 30” and W 122º 00’ 00”.


The United States Geological Survey (USGS) has many missions. At one time, a major mission of the USGS was the supplying of topographic maps of the United States on several scales. Our cache series is based on the 7½-minute quadrangle series.

The term quadrangle is used, instead of quadrilateral or rectangle, because the sides of these blocks are curved. The USGS divided the United States into quadrangles that are 7½ minutes by 7½ minutes. Since a degree is divided into 60 minutes, a quadrangle one degree by one degree contains 64 of these quadrangles.

*Census class code U5 indicates a populated & Census Designated Place.