Camp Half-Blood

Camp Half-Blood is a camp made espcially for demigods. Each demigod has a cabin for their own parent. This camp is on "Half-Blood Hill", but to mortals it appears as a strawberry farm. There is a tree called Thalia's Tree, which prevents monsters and mortals from coming in- allowing only Demigods and whoever the people who are in the camp invite in.

Thalia's Tree was made by Zeus. Thalia, Zeus's daughter, was running into camp with a few other demigods. In order to get them through, she had to go last. She did, and was attacked. She almost died, but Zeus turned her into a tree to preserve her life.