Section 23170 Of Article 3. Settlement Of Boundary Disputes From California Government Code >> Division 1. >> Title 3. >> Chapter 2. >> Article 3.

. Every common boundary between counties which has been mutually recognized and used by the counties adjacent thereto for the purpose of the assessment and collection of taxes for a period of 25 years continuously prior to July 30, 1927, is confirmed, validated, and declared to be legally established.