Hilltop Son La Prison is an important historical vestige. Some parts were destroyed by the French, and later by the Americans, but many of the ramparts have been rebuilt, and some interiors have been done over so that visitors get the full effect. The museum at the back tells -- in cases of artifacts, translated documents, pictures, and creative renderings -- the story of how prisoners marched in chains for over 220km (137 miles) and then were entombed here. (Having just gone over it by car or motorbike, think of walking the same route in chains over a 2-week period.) Expressive plaster statuary and oil paintings of scenes inside the prison express the prisoners' plight. Like many war sites or prisons in Vietnam, Vietnamese visit here as a way of remembrance, to honor and give thanks to those who have sacrificed. Find displays of prisoner shackles, photos of prison life, and weapons used by prisoners during the many uprisings, including the 1945 revolt that shut down the prison for good. The museum has a model of the prison rooms as they were, with slat beds and floor toilets. Out back, don't miss the tree of To Hieu, a survivor and the namesake of the town's main thoroughfare who returned in the 1950s and planted a small peach tree to celebrate peace. The tiny, gnarled tree is behind a wall just to the right of the entry to the main prison compound. The basement of the main prison building houses eerie solitary-confinement chambers and rebuilt "Tiger Cage" cells. Don't go alone unless you can handle the chill.
Adjacent to the prison area, there is a two-story museum in a more modern compound. You'll find rather tatty but organized displays on local hilltribe culture, a room dedicated to the life and legacy of Ho Chi Minh, and ubiquitous sun-bleached photos of industrial projects indicating Vietnam's victorious rise of the working man and progress into the next century (seen one, seen 'em all). There's also a room of stone and ancient artifacts, including some fine examples of Dong Son drums, evidence of Vietnam's earliest Bronze Age culture. Note: The promenade near the museum is more or less the city's "inspiration point" in the evening.