1995年,被定為(wei)“國(guo)際溶洞協會(hui)探險(xian)基地”(全國(guo)僅(jin)二(er)家),并被吸收為(wei)國(guo)際溶洞協會(hui)會(hui)員(全國(guo)僅(jin)三家)。
九(jiu)(jiu)(jiu)天(tian)洞(dong)(dong)因(yin)有九(jiu)(jiu)(jiu)個天(tian)窗與洞(dong)(dong)頂(ding)地(di)(di)面相通而(er)得(de)名。1987年(nian)山溶(rong)洞(dong)(dong)探(tan)(tan)險勇(yong)士(shi)王海然(ran)發(fa)現(xian),1988年(nian)正式對(dui)游人開(kai)(kai)放(fang),被列(lie)為(wei)省級風(feng)景(jing)(jing)名勝區,同(tong)年(nian),經(jing)國際(ji)(ji)溶(rong)洞(dong)(dong)組(zu)織專家考察(cha)(cha)論證,認為(wei)九(jiu)(jiu)(jiu)天(tian)洞(dong)(dong)規模龐大,景(jing)(jing)觀(guan)獨(du)特,還有一(yi)批溶(rong)洞(dong)(dong)群(qun)沒有開(kai)(kai)發(fa),適合(he)開(kai)(kai)展探(tan)(tan)險考察(cha)(cha),因(yin)而(er)正式接納九(jiu)(jiu)(jiu)天(tian)洞(dong)(dong)作為(wei)國際(ji)(ji)溶(rong)洞(dong)(dong)組(zu)織成員單位,同(tong)時確定九(jiu)(jiu)(jiu)天(tian)洞(dong)(dong)為(wei)國際(ji)(ji)溶(rong)洞(dong)(dong)探(tan)(tan)險基地(di)(di),九(jiu)(jiu)(jiu)天(tian)洞(dong)(dong)從(cong)此(ci)進入(ru)國際(ji)(ji)溶(rong)洞(dong)(dong)世界(jie),身(shen)價倍增(zeng)。經(jing)考察(cha)(cha),發(fa)現(xian)洞(dong)(dong)內有古樹化石和其它溶(rong)洞(dong)(dong)極少見的巖溶(rong)物(wu)質,不僅是難得(de)的自然(ran)景(jing)(jing)觀(guan),而(er)且有極高(gao)的科研(yan)價值。已經(jing)探(tan)(tan)明可供游覽的面積有250公(gong)頃,號(hao)稱(cheng)“亞(ya)洲第一(yi)大洞(dong)(dong)”。洞(dong)(dong)口南側(ce)2.5公(gong)里處,有集自然(ran)風(feng)光和濃(nong)郁(yu)民族(zu)風(feng)情于一(yi)體(ti)的風(feng)巒溪天(tian)然(ran)森林公(gong)園與之相依相襯;洞(dong)(dong)口東南向2公(gong)里處,澧水(shui)像條銀色飄帶,蜿蜒流(liu)過。
九(jiu)(jiu)天(tian)洞(dong)總面(mian)積達250多萬(wan)平方米,分(fen)上、中(zhong)(zhong)(zhong)、下三層(ceng),最底層(ceng)于地(di)表420米。洞(dong)內有40個(ge)大(da)廳、3條陰河、12條瀑布、5座自(zi)生橋(qiao)、6處千(qian)丘田、3個(ge)自(zi)然湖。洞(dong)中(zhong)(zhong)(zhong)石(shi)筍、石(shi)柱(zhu)林立(li),石(shi)簾(lian)、石(shi)幔(man)遍(bian)布。堆珍疊玉、千(qian)姿百態(tai)。九(jiu)(jiu)天(tian)洞(dong)被譽為中(zhong)(zhong)(zhong)國(guo)溶洞(dong)奇葩。