One of the last remaining watch towers along the old city wall, Phra Sumen Fort overlooks the river, resting in quiet dignity. Best enjoyed at sunset, when it is lit up by ground lights in the fading twilight, it's mystery is heightened by the fact that admission is not allowed. Stroll through the peaceful grounds that boast regal pavilions along the riverbank. There is a small canal that feeds into the park, where old riverboats bob among the waterlilies and a bizarrely-placed backpacker's bar is nestled on the bank like a forgotten cabin.