D&D 5E City Adventures...how?

[Baldurs_Underdark]

Session Zero = all-important
It all starts with a good session zero, where you discuss the characters and setting. It's alright if you have an idea for the general story and BBEG, but don't bother creating the initial plot hook until you know your PCs and what motivates them.

Now, it is critically important that you discuss what bonds the PCs during the Session Zero. For example they may all be orphans and know each other for a long time from the orphanage. Or they may just be friends from the pub with a love passion for ale.

The first plot hook
Once you know what bonds the PCs you can create a first plot hook which will motivate the whole party. For example some orphans went missing or that evil headmaster that they all hate so much did something bad. Or the ale from their favorite pub was stolen. From there on you can tie that plot hook into the main story, and now the party will voluntarily follow your story in a setting that's essentially a sandbox.

Little details
Then all you need to do is flesh out the important bits of the city. @Oofta wrote a post above that explains it well. Also, don't forget to make a list of 20+ random names (optionally with a basic description) so you can improvise if the PCs suddenly decide to buy flowers and you didn't create a flower shop yet. Note that if you have random names for NPC's, you automatically also have names for shops: E.g. The NPC's name is Gearon, so the shop is Gaeron's Flowers.

 

[Dried]

I'm planning all I need (important NPC, factions and location for the adventure, a few tavern and shops and other important locations per district, etc.), and for every district of the city I'm doing a random table with event which are trying to capture the look and feel of the district. Nothing too fancy and complicated, just to give life to the locations the players are in.
And of course some improvisation while playing.

 

[Paul Farquhar]

How do people interact with cities? I would suggest that most adventurers visit cities, but don't live in them. I live 12 miles from central London, but very rarely go into the city. How the adventurers perceive the city will be very different for urban and rural backgrounds.

 

[MockingBird]

So, would running the city like a hex crawl work? I mean, as long as you have enough info on the city and locations of course.

 

[delericho]

When running a city adventure, I think there are actually two strands that you need to keep in mind: there's the adventure and the city.

What I mean by that is that your adventure will involve the characters doing various things, whether that's solving a mystery, tracking down invaders, or whatever. This isn't too much different from any other adventure, and the usual techniques generally apply.

But then there's a load of other stuff that is going on because it's a city, and cities never sleep. The characters will also want to interact with those, so they really do need to be present. Ultimately, though, these are all background to the adventure itself

I think the DM needs to be prepared for both. They also need to be prepared to gently (or sometimes not-so-gently) guide the characters back to the adventure instead of getting sidetracked with everything else that's going on.

 

[Imaculata]

I love presenting my players with a big map of a city, and letting explore freely. I'll sprinkle bits of plot in their path, to keep things interesting. But I dislike heavy railroading. Of course, all this freedom also means they can miss stuff.

 

[Paul Farquhar]

So, would running the city like a hex crawl work? I mean, as long as you have enough info on the city and locations of course.

I don't think that would really capture the feel of a city. When I travel round London I go from location A to location B without paying much attention to the generic rows of housing in between. And if you are talking about a medieval-ish sized city, you would expect to be able to walk across it in an hour, so you would have very small hexes and an encounter every 100 yards.

I would just say "you travel from [Location] to [Location]. It takes about 20 minutes. On the way you encounter [random encounter]."

As already mentioned, most of those encounters should just be colour, not combat.

 

[Celebrim]

Since it is as a practical impossibility to fully document an urban environment of more than few hundred people, urban adventures require an amazing amount of improvisation. The prep work you should do is probably similar to a hexcrawl in a lot of ways just with every hex accessible simultaneously. I rely heavily on an overall district map, and random encounter tables for color and knowledge of my setting to improvise NPCs, buildings, and shops. Players will do a lot of shopping IME. If you are new to this by all means create a 'typical' tavern, alchemist, hedge mage, armorer, weaponsmith, etc. and create a few typical townhome floor plans. You can definitely use real world floor plans as inspiration for buildings.

Cities definitely benefit from having a separate encounter table for night/day. However, don't overload the night encounters with overly lethal things. People live in a city without dying every time they go out at night. Still, there are definitely urban hazards.

Except for buildings you intend to use as dungeons, you don't need a map of everything. You just need to handwave through buildings just like you do streets and start the scene in an appropriate room.

Urban adventures tend to be as much event based as location based. You write up not just encounter locations but encounter events.

You mention railroading. Railroading in an urban environment should definitely be used generously to keep the story going whenever the players have lost the plot. You've got lots of NPCs around that can be used to nudge the PCs in the right direction. Take inspiration from Detective/Police Procedural shows. If the PC's are out of clues, you can always have the villains undertake new actions that will leave more clues. Helpful NPCs can always remember something they forgot earlier or have encounters of their own and seek out the PCs afterwards. Events in the story can be moved to where the PCs are to keep them in the loop.

Keeping focus is a real problem in an urban adventure. As you detail out the city there is a tendency for your city to acquire a lot of red herrings. If you are running a sandboxy sort of campaign where the PCs pick which hooks to bite, this isn't a problem. But if you are running a more adventure path sort of game with a central villain who has a devious plot that must be stopped, this can be a problem since the PCs will encounter all sorts of factions not directly related to the plot. Make sure your adventure path has enough time built in for side quests.

 

[GMforPowergamers]

When it comes to maps, I favour a "tourist map" approach, highlighting features of interest, and not strictly cartographically accurate. Streets can be treated like trees in a forest, you don't need to map every one.

100% agree district level mapping with coloful blocks even work

Pet peeve: muggers - they are not going to attack heavily armed bands, or fight to the death!

oh god i can NOT agree more... muggers may mistake someone for an easy mark if unarmed and unarmored... but anyone picking a fight with armed mercs is beyond dumb

Overused Trope: Sewers. Whilst some very ancient cities had sewers, most did not. If the do, they are unlikely to feature iron grates, pipes and wheels. Ceramic would be more appropriate.

this i disagree with... a few anachronisms work okay... but I prefer just regular caves under the city myself

 

[Oofta]

One note on "dungeons". First, I rarely use them, haunted houses work just as well. However, some cities were built largely underground, such as Petra. Others had massive amounts of tunneling such as Orvieto in Italy. Paris has its catacombs and even London had an underground for the poorest of the poor. One of my major cities is patterned on Naples. It has a massive underground system because the city is built on top of high quality stone used for building. Rather than get stone from faraway quarries, they just dug down.

In any case, have a high level overview but start small and be prepared to improvise is still my best advice. Good luck!