| Name | Country | Feature class | Latitude | Longitude | |
|---|---|---|---|---|---|
501  | Ionisy | Madagascar, Ihorombe | stream | S 22° 47′ 0'' | E 46° 38′ 0'' |
| 502 | Ionisoa | Madagascar, Upper Matsiatra | stream | S 21° 23′ 0'' | E 46° 3′ 0'' |
| 503 | Ioninarivo | Madagascar, Upper Matsiatra | stream | S 21° 14′ 0'' | E 45° 59′ 0'' |
| 504 | Ioninarivo | Madagascar, Upper Matsiatra | stream | S 21° 2′ 0'' | E 46° 30′ 0'' |
| 505 | Ionilahy Ionilahy,Onilahy | Madagascar, Fitovinany Region | stream | S 21° 46′ 0'' | E 47° 44′ 0'' |
506  | Ionilahy | Madagascar, Fitovinany Region Manakara > Onilahy > Ionilahy | populated place | S 21° 43′ 0'' | E 47° 38′ 0'' |
| 507 | Iondriky | Madagascar, Ihorombe Ivohibe > Ivohibe > Longoza | populated place | S 22° 37′ 0'' | E 46° 45′ 0'' |
| 508 | Ionaivo Inaivo,Inanivo,Ionaivo | Madagascar, Ihorombe | stream | S 22° 56′ 0'' | E 46° 54′ 0'' |
| 509 | Ionadria | Madagascar, Ihorombe Ihosy > Analaliry > Sakamana | populated place | S 22° 47′ 0'' | E 46° 16′ 0'' |
| 510 | Ionadita | Madagascar, Upper Matsiatra Ambohimahasoa > Vohiposa > Sahamadio | populated place | S 21° 3′ 0'' | E 47° 11′ 0'' |
| 511 | Iomindry | Madagascar, Upper Matsiatra Ambalavao > Iarintsena > Iharihary | populated place | S 21° 45′ 0'' | E 46° 51′ 0'' |
| 512 | Iofika | Madagascar, Atsinanana | stream | S 19° 22′ 0'' | E 48° 40′ 0'' |
| 513 | Iofika Ambinanyranovaky,Iofika | Madagascar, Analanjirofo Vavatenina > Miarinarivo > Anamborano | populated place | S 17° 41′ 0'' | E 49° 0′ 0'' |
| 514 | Iofa | Madagascar, Atsinanana | stream | S 18° 47′ 0'' | E 48° 33′ 0'' |
| 515 | Iobaka | Madagascar, Sofia | stream | S 15° 52′ 0'' | E 48° 12′ 0'' |
| 516 | Ioalbambo Ioalbambo,Lohalambo Riviere,Lohalambo Rivière | Madagascar, Vakinankaratra | stream | S 19° 50′ 0'' | E 46° 50′ 0'' |
| 517 | Intsaka Intsaka,Saka | Madagascar, Vatovavy Region | stream | S 21° 10′ 0'' | E 48° 2′ 0'' |
| 518 | Intsaka | Madagascar, Vatovavy Region | stream | S 21° 2′ 0'' | E 47° 56′ 0'' |
| 519 | Banc Intermédiaire Banc Intermediaire,Banc Intermédiaire,Intermediaire Bank | Madagascar, MG.03 | bank(s) | S 15° 11′ 0'' | E 46° 57′ 0'' |
| 520 | Farihy Inosy Farihy Inosy,Lac Inosy | Madagascar, Sava | lake | S 13° 51′ 0'' | E 50° 8′ 0'' |
| 521 | Inosy | Madagascar, Atsimo-Atsinanana Befotaka > Ranotsara Sud > Inosy | populated place | S 23° 40′ 0'' | E 46° 49′ 0'' |
522  | Inongoa | Madagascar, Itasy Arivonimamo > Antenimbe > Antenimbe | hill | S 19° 14′ 0'' | E 47° 5′ 0'' |
| 523 | Initeraha | Madagascar, Atsimo-Andrefana Betioky District > Betioky Atsimo > Ambatofotsy Est | populated place | S 23° 57′ 0'' | E 44° 38′ 0'' |
| 524 | Ingolo Ingola,Ingolo | Madagascar, Amoron'i Mania | stream | S 20° 44′ 0'' | E 46° 6′ 0'' |
| 525 | Ingaro Ingaro,Ingato | Madagascar, Upper Matsiatra Ambalavao > Fenoarivo > Ambondrobe | populated place | S 21° 36′ 0'' | E 46° 22′ 0'' |
526  | Ingaro | Madagascar, Upper Matsiatra Ambalavao > Fenoarivo > Kilalo | locality | S 21° 34′ 0'' | E 46° 23′ 0'' |
| 527 | Ingalana Ingalana,Ingalana Riviere,Ingalana Rivière | Madagascar, Vakinankaratra | stream | S 19° 28′ 0'' | E 46° 40′ 0'' |
| 528 | Indroamitsaka | Madagascar, Sofia Mampikony > Ambodihazoambo > Ambodimanga II | populated place | S 16° 3′ 0'' | E 47° 53′ 0'' |
| 529 | Indroamita | Madagascar, Vakinankaratra Antsirabe II > Antanambao > Indroamita | populated place | S 20° 1′ 0'' | E 47° 22′ 0'' |
| 530 | Indranana | Madagascar, Fitovinany Region Manakara > Ambalavero > Lavakianja | hill | S 21° 52′ 0'' | E 47° 44′ 0'' |
| 531 | Indonto | Madagascar, Atsimo-Atsinanana Vangaindrano > Ampasimalemy > Vohilava | populated place | S 23° 23′ 0'' | E 47° 35′ 0'' |
| 532 | Îlot Indien Ilot Indien,L'Ilot Indien,L’Îlot Indien,Îlot Indien | Madagascar, Menabe | island | S 19° 48′ 0'' | E 44° 24′ 0'' |
| 533 | Torak’ Indiana I'Indien Sandbar,I’Indien Sandbar,Torak' Indiana,Torak’ Indiana | Madagascar, MG.06 | bank(s) | S 19° 48′ 0'' | E 44° 0′ 0'' |
| 534 | Inatobe | Madagascar, Analamanga Antananarivo-Atsimondrano > Antanetikely > Anjoma Fanamiana | hill | S 19° 7′ 0'' | E 47° 28′ 0'' |
| 535 | Inanobe Inamobe,Inanobe | Madagascar, Vakinankaratra Faratsiho > Faravohitra > Andrefaninanobe | mountain | S 19° 30′ 0'' | E 47° 4′ 0'' |
| 536 | Inanilaka Bas | Madagascar, Androy Ambovombe District > Sihanamaro > Ankazomanga | populated place | S 25° 12′ 0'' | E 45° 45′ 0'' |
| 537 | Inango | Madagascar, Sofia Befandriana Avaratra > Antsakanalabe > Mahalina | populated place | S 15° 33′ 0'' | E 48° 17′ 0'' |
| 538 | Inandy | Madagascar, Ihorombe Iakora > Ranotsara Nord > Ranotsarabe | populated place | S 22° 46′ 0'' | E 46° 39′ 0'' |
| 539 | Inanavy | Madagascar, Atsimo-Andrefana Betioky District > Besely > Ananavy | populated place | S 23° 24′ 0'' | E 44° 23′ 0'' |
| 540 | Inanarenana | Madagascar, Anosy Betroka > Nanarena Besakoa > Nanarena Besakoa | populated place | S 23° 39′ 0'' | E 45° 43′ 0'' |
| 541 | Inanarena | Madagascar, Anosy Betroka > Bekorobo > Nanarena Antondrotsy | populated place | S 23° 52′ 0'' | E 45° 57′ 0'' |
| 542 | Inanarena | Madagascar, Anosy Betroka > Mahabo > Ankeniheny | populated place | S 23° 37′ 0'' | E 46° 8′ 0'' |
| 543 | Inanantonana Inanantonana,Inanatonana,Inantonanna | Madagascar, Vakinankaratra Mandoto > Ankazomiriotra > Antanetikely | populated place | S 19° 39′ 0'' | E 46° 37′ 0'' |
| 544 | Inakatsa Ruisseau | Madagascar, Anosy | intermittent stream | S 24° 49′ 0'' | E 46° 26′ 0'' |
| 545 | Imotombe Sud | Madagascar, Androy Ambovombe District > Sihanamaro > Imontombe | populated place | S 25° 13′ 0'' | E 45° 42′ 0'' |
| 546 | Imorona | Madagascar, Vakinankaratra | stream | S 20° 15′ 0'' | E 46° 38′ 0'' |
| 547 | Imorona | Madagascar, Upper Matsiatra Lalangina > Sahambavy > Imorona | populated place | S 21° 28′ 0'' | E 47° 19′ 0'' |
| 548 | Imorona | Madagascar, Analanjirofo Mananara Nord > Imorona > Imorona | populated place | S 16° 12′ 0'' | E 49° 50′ 0'' |
| 549 | Imonty Emoty,Imonty | Madagascar, Anosy Taolagnaro > Ambatoabo > Talakifeno | populated place | S 24° 48′ 0'' | E 46° 41′ 0'' |
| 550 | Imontsaka | Madagascar, Anosy Amboasary > Esira > Betonta | populated place | S 24° 12′ 0'' | E 46° 37′ 0'' |
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