If you're getting this (crashes on AI's turn, when entering Industrial Age, or building an army with the leader):

CIVILIZATION3 caused an invalid page fault in
module CIVILIZATION3.EXE at 017f:00403046.
Registers:
EAX=00000000 CS=017f EIP=00403046 EFLGS=00210206
EBX=005c5818 SS=0187 ESP=00abfc30 EBP=01360eb0
ECX=0cf21e6c DS=0187 ESI=0cf21e6c FS=2b6f
EDX=0000126f ES=0187 EDI=00000000 GS=0000
Bytes at CS:EIP:
8b 80 3c 01 00 00 83 c1 58 8b 50 04 52 e8 38 71
Stack dump:
00000000 004063e3 00000000 00874440 0cf21e6c 00000002 0cf21d00 00000000 02115ca0 005c5818 bff52d9d 0cf24530 00abfc9c 00592afb ffffffff 004eab20

Try copying the patch directly into the Civ file then re-execute it.

Huh?

Do you mean to physically copy the download into the \civ subdirectory and run it from there or ?

Thanks! I really hope this is a solution. I got through an entire game, started another, then BAM! Page Fault.

Yes.
Place the patch file directly into the Civ subdirectory and run it. Can't guarantee it works for you but others (and me) had a success with it for some reason.

I have not tried that yet but I finally finished an entire game by going back to ver 1.07 and applying the crack from megagames.com.