Question

1. islands that form a protective barrier between the ocean and the mainland
2. an area with similar geographic characteristics that set it apart from surrounding areas
3. the usual weather in an area over a long period of time
4. the height of an object above a given level, usually sea level
5. a large area of elevated land that is relatively flat
6. the center of a particular activity or network

down

1. a natural landform or body of water on earth
2. the study of earths surface and climate, and of human activity, and of the interactions between them
3. one of the halves of the earth as divided by the equator or by the prime meridian
4. a geographic border between two regions, where rivers produce waterfalls
5. a measure of a locations distance north or south of the equator

Explanation:

This appears to be a geography - related vocabulary crossword. Each clue describes a geographical concept. For example, "islands that form a protective barrier between the ocean and the mainland" is a description of barrier islands; "the usual weather in an area over a long period of time" refers to climate.

Answer:

1. Barrier islands
2. Region
3. Climate
4. Altitude
5. Plateau
6. Hub

Down:

1. Landform or water body
2. Geography
3. Hemisphere
4. Fall line
5. Latitude