The islands stand on a rocky shoal with dangers extending up to 0.6 mile E and S. A light-beacon (E cardinal) (black post, red band, isolated danger topmark, 4 m in height), marks the E extremity of the danger. A beacon (isolated danger) and a light-beacon (isolated danger) mark, respectively, rocks at the SE and S extremities of the shoal. The channel inshore of the islands is deep and free from isolated dangers.