Is there a limit to the extravagance and to the amount of money the world's super-rich can spend on toys? Not when it comes to mega-yachts it would seem. UK-based company Yacht Island Design recently announced that it had designed together with BMT Nigel Gee, a 155-meter (508.5-foot) luxury yacht modeled after a section of downtown Monte Carlo and rightly named "The Streets of Monaco".

Greatly influenced by land-based architecture, the steel and aluminum vessel caries an urban replica of some of the principality's most famous metropolitan elements: There's the iconic Café de Paris, a Monaco-themed swimming pool and jacuzzi, a Casino Square, featuring a large glass-bottomed fountain in a tranquil garden setting, a spacious spa with manicure and hair salon, a dance hall, a movie theater, a gym, tennis courts, a library, a helipad, a submarine dock, and even a go-kart track inspired by the city's grand prix street circuit.

In total, this floating city can accommodate up to 16 guests and 70 crew members. It should travel at a top speed of 15 knots and is expected to cost up to £700 million (more than €800 million), making it the most expensive personal boat in the world.

This project is one of the two new concept designs Yacht Island Design is working on (the second will be a smaller 85-metre ‘yacht', based around a Pacific Island theme). In a statement, the company declared that "The art of producing a themed yacht is to seamlessly weave a story into every element of the design and is achieved via extensive consultation with the client during the initial phases of the design process."

However, now that the design has been completed, it remains to be seen whether the company can find a billionaire flamboyant enough to turn the concept into reality.

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