ðɛɹ ɪz ˈɔːlsoʊ ɐn ˈʌndɚɡɹˌaʊnd lˈeɪk ˌʌndɚ ɹˈoʊssmɚ, ˈæksɛst θɹuː ðə mˈɪlʊɚ tˈʌnəl, wˌɪtʃ pˈæsᵻz bᵻnˌiːθ ðɪ ˈɛɹiə.
There is also an underground lake under Rhosesmor, accessed through the Milwr tunnel, which passes beneath the area.