Seventy miles off Key West, Florida, lie the Dry Tortugas, which consist of 7 small islands. One of them–Garden Key– is the site of Fort Jefferson which is the country’s largest coastal fort and also the country’s largest masonry structure. It takes up 11 of Garden Key’s 16 acres. Construction started in 1846 and lasted for 30 years, mainly because each of the 11,000,000 bricks had to be brought in by boat. It was never coompleted and never was a shot fired. The lighthouse was built in 1876 and discontinued in 1921. It was on a U.S. stamp in 2009. The first photo is dated 1897 (click to enlarge), the third 1900, and the fifth 1935.

Tybee Lighthouse is located at the mouth of the Savannah River in Georgia where the river meets the Atlantic. It is 1 0f  7 colonial lighthouses still standing. Beginning in 1726 there have been 4 lighthouses on the site, the current one having been built in 1773. It was heavily damaged by the Confederates in 1862 and then rebuilt using the first 60 feet as the base. It is still active today and is considered one of the country’s most complete and well-maintained light stations. Tours are available. The first photo is dated 1885.

Sand Island Lighthouse is located 3 miles off shore from Mobile Bay, Alabama. Originally situated on 400 acres, it now sits on just 1,  It was completed in 1873 using the same plans used for Bodie Island and Currituck lighthouses on the Outer Banks. It was automated in 1948, decommissioned in 1971, and stabilized around its base in 2008. It is one of the most threatened lighthouses in the country. The first photo is dated 1873.

Point Isabel Lighthouse is located just south of South Padre Island near the Rio Grande River, which separates Texas and Mexico. The lighthouse was built in 1853 and extensively damaged by the Confederates during the Civil War. It was deactivated in 1905, but returned to service in 1955. In 2000 it was restored to its 1888 appearance. In 2005 it began showing outdoor movies projected on to the lighthouse walls (see photo five). The first photo is dated 1895 and the third is from the 1920s.

Biloxi Lighthouse on the Mississippi Gulf Coast was built in 1847. In that long history it has had the most number of female keepers of any lighthouse in the country. Such history also includes numerous hurricanes, including Katrina. Biloxi Lighthouse also has the distinction of being the only one in America to be situated in the middle of a major US highway. It was on Mississippi’s license plates from 2007 to 2012 and on a US stamp in 2009. Daily tours are available. The first photo is dated 1892 and the third is from 1909.

Key West Lighthouse is located at the tip of the southern most city in the US. It was built in 1848 and, 158 years later, still has the Fresnel lens installed in 1858 although the lighthouse was deactivated in 1969. During its years of service the same family were the keepers for over 80 years. It sits all of 15 feet above sea level and is open for tours. The first photo is dated 1865