1995年,被定為(wei)“國(guo)(guo)(guo)際溶(rong)洞(dong)協會(hui)探(tan)險基地”(全國(guo)(guo)(guo)僅(jin)(jin)二家),并被吸收為(wei)國(guo)(guo)(guo)際溶(rong)洞(dong)協會(hui)會(hui)員(全國(guo)(guo)(guo)僅(jin)(jin)三家)。
九天(tian)(tian)洞(dong)(dong)因有九個天(tian)(tian)窗與(yu)洞(dong)(dong)頂地(di)(di)面相(xiang)通而得名(ming)。1987年(nian)山(shan)溶洞(dong)(dong)探險勇(yong)士王(wang)海(hai)然發(fa)現,1988年(nian)正式對游人開(kai)放,被列為省級風(feng)(feng)景名(ming)勝區,同年(nian),經(jing)國際(ji)(ji)溶洞(dong)(dong)組(zu)織(zhi)專家考(kao)察論證,認為九天(tian)(tian)洞(dong)(dong)規模(mo)龐大(da),景觀獨特,還有一(yi)批(pi)溶洞(dong)(dong)群沒有開(kai)發(fa),適合開(kai)展(zhan)探險考(kao)察,因而正式接納九天(tian)(tian)洞(dong)(dong)作為國際(ji)(ji)溶洞(dong)(dong)組(zu)織(zhi)成員單位,同時確定九天(tian)(tian)洞(dong)(dong)為國際(ji)(ji)溶洞(dong)(dong)探險基(ji)地(di)(di),九天(tian)(tian)洞(dong)(dong)從此進入國際(ji)(ji)溶洞(dong)(dong)世界,身價(jia)倍增。經(jing)考(kao)察,發(fa)現洞(dong)(dong)內(nei)有古樹化石(shi)和其它(ta)溶洞(dong)(dong)極(ji)少(shao)見(jian)的(de)巖溶物(wu)質,不僅(jin)是難得的(de)自然景觀,而且有極(ji)高的(de)科研價(jia)值。已經(jing)探明可供游覽的(de)面積有250公頃(qing),號稱“亞洲(zhou)第(di)一(yi)大(da)洞(dong)(dong)”。洞(dong)(dong)口南側2.5公里處(chu),有集自然風(feng)(feng)光和濃郁民族風(feng)(feng)情(qing)于(yu)一(yi)體的(de)風(feng)(feng)巒(luan)溪天(tian)(tian)然森(sen)林公園與(yu)之相(xiang)依相(xiang)襯;洞(dong)(dong)口東南向(xiang)2公里處(chu),澧水像條銀色(se)飄(piao)帶,蜿蜒流過。
九(jiu)天洞(dong)(dong)總面(mian)積達250多萬(wan)平方米,分上、中(zhong)、下三層,最底(di)層于(yu)地表420米。洞(dong)(dong)內有40個大(da)廳、3條陰河、12條瀑布、5座自(zi)生橋、6處千(qian)丘田、3個自(zi)然湖。洞(dong)(dong)中(zhong)石(shi)筍、石(shi)柱林立,石(shi)簾、石(shi)幔遍(bian)布。堆珍疊玉(yu)、千(qian)姿百態。九(jiu)天洞(dong)(dong)被(bei)譽為中(zhong)國溶洞(dong)(dong)奇葩。