While impressive looking, at the time of writing all entrance to the fort has been blocked off making the draw to this spot another feature all together. In the shade of Phra Sumen Fort is Santichai Prakar Park, a tremendously pleasant place to spend an afternoon.
Particularly popular with Thais on the weekends, the park is a low-key spot to relax and river-watch, as it sits right on the banks of the Chao Phraya. Within walking distance of Khao San Road, the park is also home to a 100-year-old Lamphu tree, the very type of tree that Banglamphu (Khao San area) is said to take its name after. Monday through Fridays there is aerobics class in the park at 18:00.