U.S. cities and timezones/ state borders.

Arizona as a state does not observe daylight savings time, so for part of the year the state is one hour ahead of California. The rest of the year they have the same time as California. But the Navajo
nation lands in the NE quadrant of the state DOES observe DST. Just to add a bit of difference to an already mixed situation, the Hopi lands in the middle of the Navajo lands DO NOT observe DST

So Arizona has a strange concentric formation of areas that consecutively do not/do/do not observe DST. Weird.

In Broomfield’s case, it was incorporated wholly within Boulder County in 1961. Over the years, the city annexed land in adjoining counties with the result there were four county court systems, four county tax bases, etc. So to make everything in Broomfield consistent within all parts of the city, creating a new county was deemed to be the most efficient solution.

NW Indiana is aligned with Chicago and it is on Central Time. However, once you get to Marshall County,Indiana (Plymouth being the county seat and largest city) you are in Eastern Time like the rest of the state. Since Indiana adopted daylight savings time, it no longer experiences the three different time zones that it did in the past (Central,Indiana and Eastern)

Before Indiana did change to daylights savings, you could drive from South Bend into Michigan and leap ahead one hour. That was across the state line.

Wendover, Nevada allows gambling, but because the town itself looks east to Utah for its business dealings, the US Department of Transportation moved the time zone line so that the Nevada town is in the Mountain Time Zone. Because of the thriving gambling side of the state line, the Utah side is dying, and there have been repeated moves to merge the two towns together and move the Utah side into Nevada, but the state of Utah won’t allow it.

“Codominium”?

I’ve always wondered why it’s there in the first place. It’s not like Jackpot or Stateline where the whole town was founded just to be the first place you can gamble-- the town originally sprung up around the airbase, but I can’t figure out any logical reason why the Air Corps decided to put it right there when they had a whole big desert to choose from.

Phenix City, Alabama is just over the state line from Columbus, Georgia.

The Air Base was constructed on a bombing range. It was built in Wendover because the place was on the railroad, and because it was far enough away from any major cities that, should there be some accident, they wouldn’t accidentally bomb the civilian population.

Gosh no - my state of Indiana continues to insist with multiple time zones. Cross a county line and you may have to change your watch. If you need to call some sort of state service it pays to know if there’s a difference in time zone where you are vs. where the service office is located. It’s not quite as bad as it used to be but it’s never the same time across the entire state. Counties near a large urban area will follow that urban area even if it’s in another state, such as Lake and Porter counties following whatever time Chicago is. There’s a train line that goes from Chicago to South Bend, and the schedules have notions as to what time of the year which part of the line is following which time zone.

You still get that effect some places in the state.

As it happens, I live in part of unincorporated Lake County, Indiana. Yes, we pay fewer taxes. We also have many fewer services. For example, we have no street lights. We do not have either municipal water or sewer services so my home has its own well and septic system. There is no government monitoring of our well, if we want the water tested for quality that has to be done by us (well, by our landlord). We do not have municipal trash removal. My landlord pays a private company to pick our garbage up once a week. Other people will take it down to the dump themselves, or else try to sneak their garbage into the bins of people who do have garbage pickup, leading to such craziness as having locks on trash bins. It’s not because people are afraid of someone stealing their trash, it’s because they don’t want other people filling up their bins. Several years ago the county DID start putting in storm sewers which has reduced the annual flooding around here. The only police coverage is the local sheriff, the county-level police.

This is why I laugh whenever I hear libertarians go on about what a paradise it would be if government withered away to nothing and everything was done by private agreement and business. It’s not paradise. It’s people getting into fistfights over who is dumping whose garbage in who’s dumpster, when they’re not simply dumping it on the roadside.

Nope, condominium.

Before the mid 19th century many places in the UK had different times. With the advent of the railways, they needed to work on a standard time base so some towns would have had local time and railway time for a while. It wasn’t long before they all switched to railway time.

I believe that something similar happened in the US.

You might want to check into that further- I remember being told that about a different state ( Florida,I think) and it turned out that you had to register your vehicle if you were if you were a resident for a certain number of consecutive days - or if you lived there for any length of time and had kids in school, worked, paid resident tuition at a public college , etc.But you have to live there to be a resident, so it didn’t apply to people commuting into the state daily ( if anyone does that, I know it happens all the time in the Northeast), or people spending a few weeks there on business, and the time requirement exempted snowbirds who spend only the winter there.

The vagaries of time zones leads to this puzzle: How can a clock in an Atlantic seaboard state correctly read the same time as a clock in a Pacific state?

Western Florida uses CST (just continue the border between Georgia and Alabama south). There is a strip of eastern Oregon that is on mountain time; I assume that it is some local accommodation. So the clock in western Florida is usually one hour ahead of the one in eastern Oregon. However for one hour every year, between 2 and 3 AM central time on the night that DST ends, the clock in western Florida will be on standard time and the one in eastern Oregon will still be on DST and they will be the same.

Maybe the most anomalous time zone in the world is that of Chatham Island, a possession of and well southeast of NZ. They are east of the dateline, but a zone that is 45 minutes ahead of NZ, hence UTC + 12:45, at least when they are on standard time, which actually started last night in NZ.

Read the first bullet.

The only decent hotel in Tuba city is on Hopi land, and is on a different time zone than the rest of the city (the time changes when you cross the street).
All the cell towers are on Navajo land, so one’s phone time must be treated with suspicion.

There are FOUR time zones in the US, so I don’t see how your puzzle could possibly be correct.

I don’t see what you don’t see. Read the spoiler where it is spelled out in detail.

I also read the first paragraph which talks about residents illegally registering vehicles in other states. Thats why I suggested checking into it further - that entire page may be discussing people who live in Arizona at least temporarily rather than commuters.

Incorrect. Alaska and Hawaii provide two additional ones.

Nope. I got a ticket from MVD for working in Phoenix even though I was still a resident of California. One of our campus security officers was an asshole and reported it the first day of school even though I had moved there less than a week previously despite the statutory definition of a resident being someone who lived in Arizona for 6 months. I was told by MVD that if you work in Arizona you need to register your car in Arizona to use it. I even use the example of someone living in Laughlin, NV commuting to Bullhead City, AZ and according to MVD it doesn’t matter where they live, that’s for Nevada to worry about i.e. not their problem.