Suggest me a City Building Game

Not exactly the same but Dark Cloud has a city building mechanic.

I'm enjoying Cities XL at the moment. The Anno games are pretty good too.

SimCity 2000 is the best.

Viva Piñata Harlem Edition. It has bigger emphasis on territory control than the original game.

If you are looking for something a little more carismatic and casual game, try Demolition Inc. (Yes, it's a "destroy-cities" game, but you can also build you own cities with Workshop feature, and then destroy them!)

simcity?

It's a little more "at a per person level" but what about Settlers 2 - 10th Anniversary Edition? (the best of all the settlers games to be honest).

Well! looking through the post most of What I would have mentioned has been already but I can still throw in some that I wouldnt have posted otherwise

they are still great imo but are not quite what you specified

Hinterland (on steam) is a city builder RPG where you have to defend and strike out against marauding bandits monsters and demons while upgrading buildings, building new buildings, acquiring new resources, and fulfilling kings requests for goods. its pretty sandbox and plays sort of arcade-y. you can equip your immigrants with loot found around the world and enlist them in hunting parties when you go adventuring with your character, quite a fun game, its a shame tilted mill crapped out before they could make more of them.

Fragile Allegiance (On Gog) is a asteroid field city builder, it runs like a 4x strategy game but it has alot of emphasis on colony building, mining, trading and upgrading. There is some combat but it can be greatly mitigated by the built in diplomacy system (alien corporations vying for mineral resources). this one is one of my all time favorites, but its not quite what your looking for unfortunately.

The Movies (from... not sure) is a pure and simple city (lot) builder, no combat or any of that, its all about managing your movie studio and producing movies with your actors, crew, gaffers, grips, all of that fun stuff. this game is really brilliant and it is a shame it was pulled from steam years ago. this is probably the closest thing to what you are looking for.

Evil Genius (on steam) is a game where you play as, you guessed it, an evil genius. this one is pretty stressful and a pain in the butt at times because you have to constantly fend off the 007 agents trying to invade your lair (this is more like a less good dungeon keeper than a city builder really)

Stronghold (on steam) is a game about building a economically sufficient castle/fort/town/thing. or a defensible one. all fo these games have economic modes where you are accomplishing goals with NO fighting and military modes where you siege, or protect your castle as best you can. both involve some measure of city building, not so much sandbox unfortunately and not quite what you are looking for.

A Kingdom for your Keflings (on desura/onlive/xboxlive) is a game about building a sandbox kingdom for little npcs called kieflings. you play as the avatar dude of your choice who is super big and basically uses building parts to create different structures while your keflings gather resources. Fun but it loses its shine after a while. sandbox and citybuilder with crafting and no fighting, definately a relaxing game to play... this one fits your needs pretty well.

That's all I can think of now.

EDIT OMFG how could I forget...

Startopia (availible on GOG) is a city builder (in a space station) I'd say it has a little more in common with things like theme hospital, but Its much more like those old sierra games. You play as the space station manager either without any competition, or with up to four other managers reclaiming said spacestation (in this case you can fight otherwise its purely sandbox/goal oriented if your playing a campaign) you build buildings such as discos, hotels, med-bays, sleeping pods, power stations, recycling centers, star-docks, etc. to fulfill the needs of your startopian citizens who regularly arrive at your station. there is also a terraforming aspect where you can grow crops in a mold-able garden level to sell off to traders that periodically come to your station. one of my all time favorites right here, can be very relaxing to play, can also get hectic at times.

Civ V, age of empires online? Probably not quite the city builder your looking for

Cities XL games are nice, quite similar to SimCity. If you'd like something more like Caesar, I'd recommend: Zeus: Master of Olympus (+Poseidon add-on) - similar to Caesar series but a bit simpler and set in ancient Greece - or Pharaoh (+Cleopatra: Queen of the Nile add-on) - set in ancient Egypt, and based on the same engine as Caesar III. Both games are available at GOG for 5$ each. There's also Children of the Nile, which is also set in Egypt, but isn't as old as Pharaoh :) And it cost 5$ on GOG as well (it's also available on Steam, but costs a bit more).
You could also try The Settlers series (The Settlers 7 is available on Steam) , or Civilization (you can grab Civ3 Complete for 5$ on Steam, if you don't want to spend 5x that on Civ4 or 5).

Now, if you don't mind a game whose motto is losing is fun and barely has any graphics, you could try Dwarf Fortress. It is difficult, you will lose but once you get into it, you'll just keep playing :) You can grab it for free from the dev's website or you could google 'lazy newb pack' which is just the game bundled with some utilities (like real graphics).

Hope I helped :)

Constructor - An old game, but still great fun
Towns - Simplistic graphics, but you literally build everything from their beds to walls, to the floor.
Gnomoria - similar to towns maybe a bit more complex, I could never get into it.

Minecraft, nuff said

SimCity

not

The only thing not yet mentioned is Medieval Lords. There is combat though, unfortunately.

Edit: Another game that's reasonably close to city-building is Space Colony.

LMAO i read the title and instantly rushed in here to say " Caesar III " but got sad when you already mentioned it.... uhg i love Caesar III ive put over 2000 hours into it over the last like 15 years ... its the one game i never get bored of and can always come back to for fun