underground structure

man-made underground structure

en-US/ˌʌndɚˈɡɹæʊnd ˈstɹʌkt͡ʃɚ/
en-GB/ˈʌndəɡɹaʊnd ˈstɹʌkt͡ʃə/

دسته بندی ها:

architectural structuresubterranea