いったい一帯ittai
1.

A continuous expanse of land that is recognized as being connected or related in some way, often used to describe geographical features or specific districts.

2.

The entirety of a specific locale, encompassing not just the central area but also the surrounding regions and their characteristics, often implying a sense of uniformity or collective identity within that space.

Example:

雨があたり一帯に降っている。