Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Institute for World Understanding of Peoples, Cultures and Languages Library | Building | 13 | San Diego | 32 50 47 N | 117 16 40 W |
| Institute of Buddhist Studies | School | | Alameda | 37 52 00 N | 122 15 11 W |
| Institute of Forest Genetics | School | 834 | El Dorado | 38 44 21 N | 120 44 32 W |
| Institute of Metaphysics | Church | 73 | Los Angeles | 34 04 14 N | 118 18 21 W |
| Institute of Molecular Medical Sciences | Building | 10 | Santa Clara | 37 25 27 N | 122 08 31 W |
| Intake Campground | Locale | 2486 | Inyo | 37 14 43 N | 118 35 20 W |
| Intake Spring | Spring | 1404 | Siskiyou | 41 19 11 N | 122 07 58 W |
| Integral Mine | Mine | 1444 | Trinity | 41 08 47 N | 122 32 11 W |
| Inter-Tribal Friendship House | Building | 8 | Alameda | 37 47 50 N | 122 15 51 W |
| Interagency Fire and Visitor Center | Building | 1729 | Shasta | 40 35 07 N | 121 34 35 W |
| Interbay 1030-003 Dam | Dam | 804 | Placer | 39 01 36 N | 120 36 10 W |
| Intercommunity Hospital | Hospital | 165 | Los Angeles | 34 05 17 N | 117 53 36 W |
| Interdenominational Church of Morgan Hill | Church | 109 | Santa Clara | 37 07 41 N | 121 39 39 W |
| Interdenominational Pentecostal Church | Church | 40 | Los Angeles | 34 01 33 N | 118 19 21 W |
| Interdenominational Prayer Tabernacle | Church | 83 | Riverside | 33 36 39 N | 114 34 39 W |
| Interfaith Center | Church | | Los Angeles | 34 11 23 N | 118 18 51 W |
| Interlaken | Populated Place | 39 | Santa Cruz | 36 57 05 N | 121 44 02 W |
| Interlaken Shopping Center | Locale | 2070 | San Bernardino | 34 15 10 N | 116 53 06 W |
| Intermountain Conservation Camp | Locale | 1309 | Lassen | 41 07 23 N | 121 13 27 W |
| Intermountain Fairgrounds | Locale | 1009 | Shasta | 41 03 16 N | 121 24 09 W |
| International Academy of Santa Barbara Library | Building | 15 | Santa Barbara | 34 25 23 N | 119 41 44 W |
| International Arena | Building | 4 | San Diego | 32 45 18 N | 117 12 45 W |
| International Bank Note Society Library | Building | 492 | Riverside | 33 43 54 N | 116 57 49 W |
| International Baptist Church | Church | 102 | Santa Clara | 37 18 05 N | 122 02 28 W |
| International Bible Baptist Church | Church | | Alameda | 37 42 04 N | 122 07 00 W |
| International Christian School | School | 22 | San Francisco | 37 46 20 N | 122 25 26 W |
| International Church of the Holy Trinity | Church | 73 | Los Angeles | 34 04 15 N | 118 18 21 W |
| International Country Club | Locale | 1 | Imperial | 32 39 53 N | 115 30 42 W |
| International House | Building | 115 | Alameda | 37 52 11 N | 122 15 06 W |
| International Institute | School | 92 | Los Angeles | 34 02 32 N | 118 13 11 W |
| International Jewelry Center | Building | 82 | Los Angeles | 34 02 51 N | 118 15 09 W |
| International Park | Park | 50 | San Diego | 32 32 14 N | 117 06 28 W |
| International Raceway | Locale | 70 | Orange | 33 39 43 N | 117 44 47 W |
| International School of Theology | School | 572 | San Bernardino | 34 11 13 N | 117 15 24 W |
| International Studies Academy | School | 55 | San Francisco | 37 45 42 N | 122 24 14 W |
| International Theological Seminary | School | | Los Angeles | 34 04 02 N | 118 02 11 W |
| International Tower Heliport | Airport | 77 | Los Angeles | 34 02 47 N | 118 15 48 W |
| International Trail | Trail | 685 | Marin | 37 55 42 N | 122 35 48 W |
| Inverness | Populated Place | 12 | Marin | 38 06 04 N | 122 51 25 W |
| Inverness Branch Marin County Free Library | Building | 13 | Marin | 38 05 51 N | 122 51 13 W |
| Inverness Park | Populated Place | 41 | Marin | 38 03 50 N | 122 49 22 W |
| Inverness Post Office | Post Office | 13 | Marin | 38 05 49 N | 122 51 07 W |
| Inverness Ridge | Ridge | 294 | Marin | 38 06 06 N | 122 53 13 W |
| Inverness School | School | 29 | Marin | 38 05 55 N | 122 51 21 W |
| Inverness School | School | 51 | Santa Clara | 37 20 31 N | 122 01 12 W |
| Invincible Rock | Bar | -3 | Contra Costa | 37 57 21 N | 122 26 22 W |
| Inwood | Populated Place | 634 | Shasta | 40 31 27 N | 121 57 26 W |
| Inwood School | School | 584 | Shasta | 40 30 49 N | 121 58 30 W |
| Inyo Camp | Locale | 1406 | Inyo | 37 09 07 N | 118 19 37 W |
| Inyo County | Civil | 1386 | Inyo | 36 35 00 N | 117 25 03 W |
| Inyo County Courthouse | Building | 1199 | Inyo | 36 48 08 N | 118 11 57 W |
| Inyo County Free Library | Building | 1198 | Inyo | 36 48 08 N | 118 11 56 W |
| Inyo County Sheriff Search and Rescue Heliport | Airport | 1254 | Inyo | 37 21 56 N | 118 22 06 W |
| Inyo Crater Lakes | Lake | 2475 | Mono | 37 41 31 N | 119 00 41 W |
| Inyo Craters Campground | Locale | 2519 | Mono | 37 41 33 N | 119 00 37 W |
| Inyo Creek | Stream | | Inyo | 36 35 54 N | 118 10 47 W |
| Inyo Heights High School | School | 1400 | Inyo | 37 09 04 N | 118 19 33 W |
| Inyo King Prospect | Mine | 1820 | Inyo | 36 55 21 N | 117 58 33 W |
| Inyo Mine | Mine | 1241 | Inyo | 36 29 50 N | 116 42 03 W |
| Inyo Mountains | Range | 1363 | Inyo | 36 10 00 N | 118 00 03 W |
| Inyo Mountains Wilderness | Reserve | 2290 | Inyo | 36 46 40 N | 117 57 10 W |
| Inyo National Forest Supervisors Ofiice | Locale | 1266 | Inyo | 37 22 20 N | 118 23 48 W |
| Inyo Queen Number 1 Mine | Mine | 1749 | Inyo | 36 55 14 N | 117 58 19 W |
| Inyo Queen Number 2 Mine | Mine | 1371 | Inyo | 36 55 01 N | 117 56 31 W |
| Inyo Well | Well | 783 | Kern | 35 35 47 N | 117 49 01 W |
| Inyo-Mono Ecology Center | Locale | 1393 | Inyo | 37 23 38 N | 118 32 55 W |
| Inyokern | Populated Place | 742 | Kern | 35 38 49 N | 117 48 45 W |
| Inyokern Airport | Airport | 745 | Kern | 35 39 31 N | 117 49 49 W |
| Inyokern Baptist Church | Church | 744 | Kern | 35 38 41 N | 117 48 48 W |
| Inyokern Church of Christ | Church | 728 | Kern | 35 38 54 N | 117 44 48 W |
| Inyokern Community Methodist Church | Church | 739 | Kern | 35 38 60 N | 117 48 49 W |
| Inyokern County Park | Park | 745 | Kern | 35 38 40 N | 117 48 52 W |
| Inyokern Elementary School | School | 743 | Kern | 35 38 44 N | 117 48 56 W |
| Inyokern Post Office | Post Office | 742 | Kern | 35 38 48 N | 117 48 45 W |
| Inyokern Senior Citizens Building | Building | 745 | Kern | 35 38 38 N | 117 48 46 W |
| Inyokern Town Hall | Building | 740 | Kern | 35 38 56 N | 117 48 51 W |
| Iodine Prairie | Area | 1777 | Siskiyou | 41 31 01 N | 121 36 02 W |
| Iodine Spring | Spring | 506 | Riverside | 33 36 50 N | 117 14 14 W |
| Ione | Populated Place | 91 | Amador | 38 21 10 N | 120 55 58 W |
| Ione Canal | Canal | 338 | Amador | 38 23 31 N | 120 49 41 W |
| Ione Canal | Canal | 316 | Amador | 38 21 15 N | 120 51 03 W |
| Ione City Hall | Building | 90 | Amador | 38 21 11 N | 120 56 00 W |
| Ione Community United Methodist Church | Church | 91 | Amador | 38 21 01 N | 120 56 03 W |
| Ione Elementary School | School | 97 | Amador | 38 20 59 N | 120 55 51 W |
| Ione Grammar School (historical) | School | 99 | Amador | 38 21 08 N | 120 55 52 W |
| Ione High School | School | 89 | Amador | 38 20 58 N | 120 56 12 W |
| Ione Junior High School | School | 94 | Amador | 38 20 54 N | 120 56 04 W |
| Ione Olson Elementary School | School | 24 | Monterey | 36 41 33 N | 121 47 36 W |
| Ione Post Office | Post Office | 90 | Amador | 38 21 09 N | 120 56 02 W |
| Ione Protestant-Community Cemetery | Cemetery | 104 | Amador | 38 20 52 N | 120 55 56 W |
| Ione Valley | Valley | | Amador | 38 21 35 N | 120 59 34 W |
| Ionian Basin | Basin | 3362 | Fresno | 37 05 36 N | 118 40 45 W |
| Iowa Canyon | Valley | | El Dorado | 38 46 17 N | 120 42 13 W |
| Iowa City | Populated Place | 59 | Yuba | 39 17 30 N | 121 28 39 W |
| Iowa Ditch | Canal | 94 | Fresno | 36 36 10 N | 119 40 07 W |
| Iowa Hill | Populated Place | 872 | Placer | 39 06 31 N | 120 51 34 W |
| Iowa Hill | Summit | 868 | El Dorado | 38 46 14 N | 120 41 27 W |
| Iowa Hill Ditch | Canal | 1657 | Placer | 39 11 50 N | 120 33 54 W |
| Iowa Hill Divide | Ridge | 1437 | Placer | 39 08 10 N | 120 42 24 W |
| Iowa Hill Mine | Mine | 912 | Placer | 39 06 36 N | 120 50 34 W |
| Iowa Hill School | School | 869 | Placer | 39 06 30 N | 120 51 34 W |
| Iowa School (historical) | School | 92 | Fresno | 36 35 28 N | 119 40 22 W |
| Iowa School (historical) | School | 104 | Sonoma | 38 14 58 N | 122 44 31 W |
| Ipp Adelanto Heliport | Airport | 911 | San Bernardino | 34 32 52 N | 117 26 14 W |
| Ira J Chrisman Wind Gap Pumping Plant | Locale | 212 | Kern | 35 00 58 N | 118 58 46 W |
| Iranian Christian Church | Church | 58 | Santa Clara | 37 15 29 N | 121 54 19 W |
| Irby Park | Park | 2 | Orange | 33 43 11 N | 118 00 42 W |
| Iredell Canyon | Valley | | Los Angeles | 34 07 54 N | 118 23 29 W |
| Ireland Creek | Stream | | Tuolumne | 37 49 32 N | 119 16 41 W |
| Ireland Lake | Lake | 3274 | Tuolumne | 37 47 20 N | 119 18 17 W |