That's a fantastic question, and one that parks departments, school administrators, and business owners grapple with constantly. After years of reviewing municipal equipment, I can tell you there's no single "most" vandal-proof can, but a combination of design principles creates the champions. The goal isn't just to survive a kick; it's to deter attempts entirely.
The top contenders are almost always heavy-gauge stainless steel or powder-coated galvanized steel. These materials resist cutting, burning, and denting far better than plastic. Look for a seamless, rounded body with minimal edges—this removes easy handholds and graffiti surfaces. The best models feature fully internal, tamper-proof hardware. Think of bolts and hinges accessible only with a special security key, preventing disassembly.
The lid is critical. A heavy, spring-loaded, close-fitting lid is ideal. It's frustrating to pry open and slams shut, discouraging dumping of non-trash items. For high-risk areas, a locking bar mechanism that secures the liner bag inside is a game-changer, preventing theft of the entire bag.
Finally, installation is everything. The most robust can is useless if it's not permanently anchored into concrete with massive core-drilled anchors. A truly vandal-proof system is a fortress: immovable, impenetrable, and frustratingly boring for vandals to target. The winner isn't a specific brand, but any can that masterfully combines these elements of material, design, and secure installation.