The structure of Fort Pilar looked a lot like Fort San Pedro in Cebu. For Pilar was built in 1635 during the Spanish era. Alongside the fort is the outdoor shrine of Our Lady of Pilar. A statue of Our Lady of Pilar was added in 1734. My friends shared that in September 21, 1897, an apparition of Our Lady of Pilar was seen standing over the Basilan Strait commanding waves to stop its rush towards Zamboanga, stopping a tsunami from ruining the city. Arnel told me that they believed that she was miraculous and many devout Catholics come to pray at the shrine.
This is the area where you light your candles. There is a prayer by the cross which you can use to make your requests. Light the candles after praying. Locals usually bring the smoke from the candles close to the body part they requested for healing.
Tip: buy candles at the pasalubong center across the street
More about Fort Pilar at http://en.wikipedia.org/wiki/Fort_Pilar