Cities XL allows gamers to develop cities on realistic 3D maps using an incredible collection of unique structures and monuments based on American, Asian and European-influenced architectural styles. The maps feature a variety of environments: mountains, hills, canyons, beaches and islands, all set in different climates from tropical to desert, Mediterranean to temperate. Players must create the right combinations of social services, leisure activities, special events and other job opportunities within their cities in order to feed, clothe, employ and entertain their citizens. Be it planning and building a new zoo, public park, residential neighborhood or transit system - there's always a fresh and exciting challenge for would-be city managers and mayors in Cities XL.

In Cities XL, the main game will be a city builder: You will be the mayor of a city and you must try to regulate its development. We say “try” because you will not have 100% control over what happens in your city – the city simulation will have a certain autonomy, combining both unyielding logical rules (the public sector) and decisions taken by independent entities (the private sector). It is this simulation that we will describe here. This article will be spread over several blog entries.

1.1 Resources

The simplest rule has to do with resources. Some buildings will supply one or more resources, while other buildings will consume them. First and foremost, there will be resources useful to the city: electricity, fuel, water, waste management. Then there will be industrial resources: agriculture, industry (heavy, manufacturing, high-tech), and services (hotels, and “offices” that represent the tertiary services – finance, the legal profession, marketing, and research). Finally, there will be transport.

Players will not necessarily have to establish a fine balance between supply and demand for each of these services. They will however have to keep an eye out for potential imbalances. For example, a resource that is in too short supply will see its price rising, which can have a negative effect on the businesses that use it. This will reduce the city’s tax income or, worse, result in bankruptcies. If electricity is too expensive, it could result in heavy industry moving out of the city. In contrast, a resource that is over-supplied will see its price collapse. This could have an effect on the industries that produce it.

1.2 Services

Other buildings will provide services to the population. This category includes education, health, the police, the fire department, shopping, and leisure. The bigger and wealthier the city becomes, the more demanding the citizens will be in terms of the quality, quantity, and variety of services available nearby. Residents will take into account the distance that separates their home from a building providing a service. This distance will be calculated based on roads and transport facilities. It’s not much use being close to a hospital as the crow flies if you’re actually on the other side of a river and there’s no bridge… Ease of access to a hospital for different inhabitants, taking roads and traffic into account. Similarly, traffic jams will in effect increase the distance from a service. Players will therefore need to improve the transport infrastructure by building highways and providing bus services.

1.3 Living environment

The third important factor will be the living environment. In this context, certain buildings will have a negative impact: buildings that emit pollution or make noise, industrial dangers, and abandoned buildings. Others will have a positive impact: nature in the vicinity of the city, parks, and monuments.
The living environment will be an important factor in citizens’ satisfaction levels. It will be easy to control at the start of the game, but will become more complicated as the city grows.

Transport will play a key role in Cities XL. It will take two forms, transport within a city and transport between cities.

2.1 Internal transport
Most citizens will have a job that they have to go to and come home from every day. Plus, as we’ve already seen, they will have access to shops and service providers. All of this activity will pass through the road network, with each citizen choosing the best route available. To avoid the almost inevitable traffic problems, players will have to improve their transport networks by building roads with more lanes, or even highways. They will also have to build bus lines and subways. But the transport network will have to be logical in design: to work efficiently, bus lines will have to link residential zones with industrial or office zones. Citizens will only use public transport if they can find routes that bring them rapidly to their workplace, with at most one or two changes. Players would be advised to fund public transport in such a way as to keep waiting times at stations to a minimum. Their citizens will be grateful to them! A good transport network will improve access to service buildings (schools, hospitals, etc.), which will in turn become more efficient.

2.2 External transport

The city that you will build won’t be cut off from the rest of the world. There will have to be a way to export the goods that it produces and import the goods that it consumes. Maps of 10 x 10 km will have zones called CityLinks around their edges. Players will have to provide roads or highways up to these CityLinks. Each CityLink provides the city with a “freight” resource. A city with low freight resources will severely penalize its businesses. So, as your city grows, you will have to improve its freight capacity. However, you will have to be careful not to develop too quickly, as each CityLink opened up will increase the number of trucks on your roads and cause traffic problems that you could well do without…
You will have access to two types of freight resources: regular freight and passengers. Regular freight refers to industrial resources. It comes via road, rail, and air. Passenger capacity will be important for your offices, your tourism sector, and… vacations for your own citizens.

The game’s online features and services will allow players to create interconnected cities on virtual and persistent planets. Mayors can share and trade with one another, specialize their economy and team up with befriended cities to create sprawling metropolises. Life on the planet will be punctuated by events and competitions - a concert held in one town may, for example, be attended by visitors from other areas who can also enjoy a walk around the city to admire the urban creations of multiple players. By combining a fantastic single-player game with the social and multiplayer aspects of an MMO, Cities XL will shape the future of the genre by offering more variety, bigger cities and multiple gameplay layers.

Cities XL is currently scheduled to ship in 2009.