Swashingtondc.7z

You can use 7-Zip on any computer, including a computer in a commercial organization. You don't need to register or pay for 7-Zip. Does 7z compress better than zip? - Microsoft Community Hub

: Uses the LZMA compression algorithm to significantly reduce the size of large geospatial datasets, making it easier to download and store than standard ZIP files. SwashingtonDC.7z

The file refers to a compressed archive typically used in geospatial or city planning data contexts, specifically for the City of Washington, DC . You can use 7-Zip on any computer, including

: The 7z format can split very large city models or datasets into smaller parts for easier transfer. specifically for the City of Washington