So, you plan to go long distance hiking in Monaco, the tiniest country in the world but one....? If you really think we're round the bend, you've got it wrong! Better head for Vanuatu to take a walk. We could of course recommend the Monte Carlo circuit with blinkers on, weekdays and at your own risk that is.
But wait, h'm, we do have a "small" suggestion: the E7 European long distance trail. On the way from Portugal to Romania, you actually pass through the miniature city-state of Monaco. Just don't walk too fast or you'll miss it.