San Juan Capistrano's list of officially designated historic sites is entitled the Inventory of Historic and Cultural Landmarks (IHCL). The Mission and downtown buildings, the Los Rios Street Historic District east of the train depot, homes in the early 20th century Mission Hill-Mission Flats neighborhood east of the library, several 18th/19th century adobe buildings, 19th/20th century ranch and farmhouses and several other historic buildings and sites are on the IHCL. San Juan also has 13 sites or districts listed in the National Register of Historic Places.

The following link takes you to a brochure which explains how to designate a property on the IHCL, including the submittal requirements and the decision-making process: Your Guide to Understanding the Inventory of Historic and Cultural Landmarks (IHCL).
The following are links to the City Council Policies regarding Historic Preservation, which supplement the City’s Municipal Code Section 9-2.327
and CEQA Guidelines requirements. The policies address a broad range of preservation issues including archaeological monitoring for development projects, reports for potentially historic sites, modifications to designated historic sites, and historic depiction programs that are required for new non-residential projects.