The whalebone you may or may not bring to mind, is really baleen, the filtering system inside a whale's mouth. The whale bone you see in this postcard is an archway made from a whale's jawbone.
The Alameda Gardens, where you can see this archway even today, was created in 1815 as an area for recreation in Gibraltar. The archway was put up in 1842 but unfortunately the gardens fell into disrepair over time. It wasn't until 1991 that they were rescued and made into botanical gardens. This year in June the Earl and Countess of Wessex (Prince Edward and his wife) visited the Alameda Gardens and were met by the director at the Whalebone Arch.
The postcard dates from before 1902 because it is an "undivided back" card with no room for a message unless alongside the picture.
A post for Sepia Saturday. A click on the button will take you to the blog.