explore dungeon/cave sealed for 10000 years ago
Tutankhamen's tomb
find ancient sword that's sharper and more durable than the sword you bought that was forged by a modern smith
Chinks literally did a revolution whit swords dug up from the first emperor's tomb
same with ancient armor, and it also fits you perfectly
Go to a museum
candles and torches are still lit
That's silly i suppose
traps still function
People can still get poisoned from chemical powders the builders spread all over the place, see Mayan tombs
fresh edible food
That's also silly, although honey can last centuries or more if properly sealed
fire arrows
Just coat them with pitch, lit and shoot