Unique technology was used in constructing the tunnel under the river Vltava: The concrete tunnel tubes were made in a dry dock on the shore, the riverbed was excavated and the tubes were then laid down into the pits.
juːnˈiːk tɛknˈɑːlədʒi wʌz jˈuːzd ɪn kənstɹˈʌktɪŋ ðə tˈʌnəl ˌʌndɚ ðə ɹˈɪvɚ vˌiːˈɛltˈɑːvə: ðə kˈɑːŋkɹiːt tˈʌnəl tˈuːbz wɜː mˌeɪd ɪn ɐ dɹˈaɪ dˈɑːk ɔnðə ʃˈoːɹ, ðə ɹˈɪvɚbˌɛd wʌz ˈɛkskəvˌeɪɾᵻd ænd ðə tˈuːbz wɜː ðˈɛn lˈeɪd dˌaʊn ˌɪntʊ ðə pˈɪts.