Depending how you get there, it will vary. If you do it NPC way,
[@main]
#IF
checklevel 34
#SAY
You're too high to enter this cave\
You are not permitted for access\
<Exit/@exit>
#ELSEACT
goto @next
break
[@next]
#if
Checklevel 30
#SAY
You may enter my cave, your at the correct level\
3 more levels to go and entry will be denighed from me\
you can <Enter the cave/@soul> now!\
<Exit/@exit>\
#ELSESAY
You're not high enough to enter this cave\
On your way\
<Exit/@exit>
[@soul]
#SAY
This cave will be a challange, i can only wish you good luck\
GoodLuck, best of luck!\
<Go, into the Cave/@move>\
[@move]
#IF
mapmove <MapNumber>
give townteleport 1
break