Postmiles are valid postmile points at 0.1 (1/10th) mile intervals, based on the Caltrans Linear Referencing System. Exceptions that are included are the beginning and ends of routes (and other situations) that don't necessarily begin or end on the even 0.1 mile interval. This geometry is based upon the extraction from TSN on 8 June 2025. . Route geometry updates based upon this extraction include routes 3, 36, 38, 49, 89, 139, 174, and 221. All updates received an update date of 6/8/2025 except for route 221 which received a date of 7/1/2025.