The Miami Beach boardwalk is genuinely one of the better accessible beach experiences I've found — Smooth concrete, wide paths, accessible ramps to the beach every few blocks. Really well done.

Ocean Drive itself is trickier. The sidewalks are narrow with outdoor dining blocking paths constantly, and most of those art deco buildings aren't ADA compliant. Lincoln Road pedestrian mall is much better if you're using mobility aids.

For actual beach access: free beach wheelchairs at several locations, and the boardwalk connects to accessible parking at South Pointe and mid-beach. Call ahead to reserve if you can.