The node on Elsa Widenmann Elementary is among the 2 northernmost nodes in the Vallejo subnetwork, and can in some ways be viewed as a sister node to the one found on Dan Mini Elementary. The Elsa Widenmann node is located northeast of the juncture of CA 29 and CA 37, and comparison between this and the Dan Mini node, which is located on the other (west) side of CA 29 gives greater insight into emissions generated by traffic on both of these busy regional freeways.