To be the highest and best use, the possible use must be physically possible:
The location and site may be ideal for the proposed improvements but lack necessary utilities or be too small to accommodate the improvements.
Frontage, depth, access, topography, and other features may preclude the intended improvements from being the highest and best use.
Example: A site on Peachtree Parkway is ideal for a Hilton Hotel. The Hilton Hotel requires 8 acres and the site is only 6 acres. Unless assemblage is possible, a Hilton Hotel cannot be the highest and best use. Be aware that a Hilton Hotel cannot be the highest and best use but another hotel that requires only 6 acres could be the highest and best use.
Topography is the configuration of the surface of the land.