located_in Territory of Guam Guam An island which is the southernmost island in the Mariana island chain and is the largest island in Micronesia. The highest point in Guam is Mount Lamlam, which is 406 m. The island of Guam is 48 km long and 6 km to 19 km wide. GAZ GAZ:00006933 GAZ:00006933 Guahan {language: Chamorro} Territory of Guam Guam An island which is the southernmost island in the Mariana island chain and is the largest island in Micronesia. The highest point in Guam is Mount Lamlam, which is 406 m. The island of Guam is 48 km long and 6 km to 19 km wide. GAZ GAZ:00006933 GAZ:00006933 Guahan {language: Chamorro}