If you are staying overnight at the Lighthouse Center you will want to bring the following with you as they are not provided.

All rooms are hostel style. 2 beds to a room and 2 rooms share a bathroom in the middle.

Pillow
Sheets
Blanket/sleeping bag
Towel & washcloth
Toiletries (including soap)
Clothing of varying weights/layers
Sturdy shoes 

You also might want to consider these Optional Items:

Binoculars
Bug spray
Flashlight
Sunglasses
Hat/visor
Water shoes
Sunscreen
Camera