Rama III Park
This park was built to honor King Rama III, who started both the Golden Mount and Wat Ratchanadda. The park consists of formally planted gardens, a statue of King Rama III and a beautiful gilded Thai styled pavilion.
Beyond the park along the main boulevard is the Ratanakosin Exhibition Hall, a new (in 2010) museum recounting the history of the royal city area. Tours of the museum are guided only and can take a couple hours, and there are a couple of coffee shops on the ground floor if you're in need of refreshment.