Google has added a simple, but useful feature to Sheets: a range name box. If you click to the left of the formula bar, the new dropdown shows your current ranges in the sheet, as well as an option to manage new ranges.
The dropdown shows each range you currently have, which, when clicked, will show all of the coordinates included in that range. The "Manage named ranges" option allows you to create new ranges quickly and easily, as well as manage your current ones. It's a nice feature add that is non-invasive if you choose not to use it.
The range name box is rolling out now. It'll be fully deployed to Rapid Release domains within 1-3 days, though Scheduled Release domains could take up to 15 days to receive it.