After you pass the gates you will have to battle Zeus and after that you will win the island medallion from his daughter.
You have to get Hercules to open it.
hes a god
When you convince Hercules he smashes the lock for you
You can't without him.
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There is no key when you get Hercules he brakes the lock
you spend it on a air balloon once you get past the gate
You don't get in until you have collected all of the five sacred items. After that Hercules is convinced to help you and he smashes the gate open.
See Aphrodite and pass her test.
The key to the gate on Mythology Island in Poptropica is located inside the Tree of Immortality, which is found in the Grove of Temples. You need to solve puzzles and defeat enemies to reach the Tree and obtain the key.
You have to spell out the word TEN with the bones.