Short search seemed to confirm my thoughts. Most ancient sites are not guarded by elaborate traps or secret riddles to get in. From what I’ve found there were some crossbows here and there. Some rare hidden rooms with a lot treasure, but again, no traps.
Step 2. Hide the money
Step 3. Think of riddles that can’t be solved with a hammer.
Step 4. Build a massive underground structure with tunnels, caves, catacombs, lava, angry spiders and secret doors.