Thus, it is a major route for travelers heading directly from the San Francisco Bay Area to the Shasta Cascade and the Pacific Northwest.

From there, it travels north about 10 miles (16 km) through rural areas near the western edge of the Sacramento Valley before reaching Winters.

After leaving that city, the Interstate then proceeds north through rural areas again for about 20 miles (32 km) until it reaches its northern terminus with I-5 near Dunnigan.

For its entire length, I-505 is a four-lane freeway (two lanes in each direction) with a maximum speed limit of 70 mph (110 km/h), which is typical for rural Interstates in California.

[5] However, I-5W and most of the other Interstates around the country with directional suffixes were eventually renumbered or eliminated, except I-35E and I-35W in Texas and Minnesota.