word | | Terrain |
| interiors | Comoros | volcanic islands, interiors vary from steep mountains to low hills |
| interiors | Netherlands Antilles | generally hilly, volcanic interiors |
| interiors | Saint Kitts and Nevis | volcanic with mountainous interiors |
| intermontane | Morocco | northern coast and interior are mountainous with large areas of bordering plateaus, intermontane valleys, and rich coastal plains |
| interrupted | Arctic Ocean | ... landmasses; the ocean floor is about 50% continental shelf (highest percentage of any ocean) with the remainder a central basin interrupted by three submarine ridges (Alpha Cordillera, Nansen Cordillera, and Lomonosov Ridge |
| interrupted | Egypt | vast desert plateau interrupted by Nile valley and delta |
| interrupted | Nicaragua | extensive Atlantic coastal plains rising to central interior mountains; narrow Pacific coastal plain interrupted by volcanoes |
| interspersed | Dominican Republic | rugged highlands and mountains with fertile valleys interspersed |
| interspersed | Finland | mostly low, flat to rolling plains interspersed with lakes and low hills |
| interspersed | Iceland | mostly plateau interspersed with mountain peaks, icefields; coast deeply indented by bays and fiords |
| Iran | Iraq | mostly broad plains; reedy marshes along Iranian border in south with large flooded areas; mountains along borders with Iran and Turkey |
| Iran | Turkmenistan | flat-to-rolling sandy desert with dunes rising to mountains in the south; low mountains along border with Iran; borders Caspian Sea in west |
| Iranian | Iraq | mostly broad plains; reedy marshes along Iranian border in south with large flooded areas; mountains along borders with Iran and Turkey |