What’s left of the original site of La Vega are the ruins of the fort Christopher Columbus ordered to be built and a church. After the great earthquake of 1562, most of what remained of the structures was taken away to build modern-day La Vega. With some imagination and the help of a guide (Spanish-speaking only), it’s possible to begin to grasp the historical implications of what you’re seeing.
A small museum at the back of the site contains Taíno and Spanish tools, weapons and ceramics. Admission and guide fees seem open to negotiation and depend on the number in your party. When we were there it was closed for renovations, and the guard couldn't say when it would reopen.
To get here, continue around 4km past the turnoff for Santo Cerro and look for an old, battered sign on the left-hand side of the road, next to an army building helpfully painted in camouflage.