The one at your left is the Boromaphiman Hall, which was built by King Rama V for Crown Prince Vajiravudh as his residence. The next two kings also resided here. But after King Ananda Mahidol died of a gun wound in the building. His Majesty the present King Bhumibol, moved to the suburban Chitralada Palace. And the Boromaphiman Hall is now used to accommodate guests of the King and is inaccessible to the public.