That's a fantastic question. It takes me back to a project in a particularly challenging downtown park. The most effectively vandal-proof design I've ever seen wasn't about high-tech locks or complex mechanisms. It was about sheer, passive, psychological deterrence through brute-force design.
The bin was essentially a massive, precast concrete cylinder, weighing several hundred pounds. It was anchored deep into a concrete foundation. The actual metal refuse container was *embedded* within this concrete shell, with only a narrow, circular opening at the top for trash. This opening featured a heavy, angled stainless steel collar.
The genius was in its simplicity. You couldn't tip it over. Spray paint on the rough concrete surface was easy to power-wash off. The angled collar made it impossible to use the top as an ashtray or to pile rubbish around it. Setting fire to the contents inside the deep, metal liner was nearly impossible. It offered no flat surfaces for stickers, no edges to pry at, and no satisfying "clang" if you hit it. It presented no interesting challenge to vandals—it was just a boring, immovable rock.
While not suitable for every streetscape due to its aesthetic, it solved the problem perfectly for that location. It taught me that the most vandal-proof design often subtracts opportunities rather than adding complex protections. It's a lesson in resilience through uninteresting, immutable form.