Historic Lemon Street is one of the better downtown walks in Palatka, with older commercial buildings, murals, storefronts, and a sense of the town's river-era prosperity. It gives visitors something specific to do between the St. Johns River waterfront and the surrounding historic districts.
The street is not a single museum-style attraction, but it is a useful anchor for exploring central Palatka on foot. Look for architectural details, public art, and local businesses rather than expecting a polished heritage precinct.