Why odd entries in the search results?

The data in the map for locations is not always accurate. I know someone else will give a more detailed reason why because I can't give you the exact reason at this time.

Happen's here to. But surprisingly, I end up using this data aswell.

... I thought about redoing the Marathon Gas POI. After looking at Marathon’s station locator website, and using Google maps to do a location search, I quickly gave up on the idea. The first one that I checked on was nothing but an empty field. I thought okay and continued, a couple more entries down, same thing. I thought, this will take forever and quickly gave up the thought of updating the POI. Apparently, these companies don’t have any idea as to where they have physical facilities and maybe, they don’t even care. Maybe it’s too much of a hassle for them to update their data base. That’s been my experience.

I was in Oceanside and wanted to go to Costco. I put Costco in the GPS and it took my to Hewlett and heading west. I finally put Costco in my phone and got directons from Google maps and it took my back to where i came from and to my destination. Very strange directions. I always thought I could trust the Nuvi but now I have doubts.

Just had another trip where Waze and the Nuvi gave opposite directions. Nuvi wanted me to turn right and Waze left. I followed Waze and got to my destination. Not sure where Nuvi was taking me.

same experience with my Toyota nav system and 3597 Nuvi = I trust the nuvi. The Toy system is pretty bad. BUT I have had a 1490 give me directions to places I never entered.

The nuvi and waze difference might be explained by different nav priorities like avoidance or faster route or scenic route.

The Costco issue could be the POI file. I would check that first b4 you blamed the hardware.

The search for Costco was on the Nuvi, it wasnt a separate POI file although maybe I should add that to my other POI files.

There are 2 problems here.

First let me address the POI problems. In the early days of this site it was very common for a user to obtain a list of "Brand Name" sites by going to the "Brand Name" website and copy and paste a list into a text editor or spreadsheet and then manipulate the data into the proper format. The user could then use an online program (GPS Equalizer?) to obtain the L/L of the addresses. These locator programs used data from Google Maps, and still do (others as well). The early data from Google Maps, and others, had a lot of errors. This was due to the MASSIVE amount of data that had to be entered as quickly as possible. Addresses were "calculated" by entering the first address and the last address on a block and then approximating the address location of the lots in between. Mapmakers are now using the city and county digital maps to identify the street address and the lot lines as well. Zoom in while in Google maps ("Map" view Not "Satellite" view) in a city and you can see the "Lot Lines". Note: not visible everywhere.

Note: Most sites now use a fancy "Locator" program to list/show the sites. A text list of locations seems to be made of "Unobtainium" these days. The usual response to an email is "There is no list". But I'll bet that somewhere in accounting that there is one in the "Assets" department. Also, just how does the site's webmaster maintain the "Locator" page?

There were also a lot of L/L errors in the street maps used. These 2 errors combined could cause the POI file's L/L to be way off. AND - don't forget FATFINGER errors by the user. I myself have created plenty! Many of the map "Embedded POIs" are wrong due to Fatfingers, location program errors or the place went out of business and wasn't removed from the GPS map.

So, if a file was created quite a while ago, it could have errors that were never caught and corrected. This is why you may wind up in a housing development instead of your desired location. This happened to me a few times while traveling and is very embarrassing, if you have passengers.

Second item - Routing errors. When I first got my Nuvi 660 for Christmas in 2008, the first long trip we made was to Atlantic City. I entered the location of the casino there and and selected "GO". Low and behold it took the route that we wanted to go - across the Bay Bridge Tunnel, up the Eastern Shore and then across the Delaware Bay on the ferry. What a lot of folks don't know is that each new map released also contains the latest "Routing Algorithms" specific to that model. It wasn't long before Garmin "improved" the algorithms and suddenly the 660 wanted us to drive up I-64 to I-95 then use the Atlantic City Expressway to get to AC. Well there is always construction on I-95, always a wreck somewhere and lots of "White Knuckle" driving. NOT a preferred route. Also, my 3597 always picks that route. The complexity of the algorithms is making it very difficult for the GPS to always pick the best route. Add in "Traffic" and that complicates things further. One time on the way to the "Preakness" race, the 660 wanted me to get on U.S. 1 at Ashland, VA. It seems that a traffic accident 70 miles ahead caused it to "Reroute" us. Well, I had "Traffic Avoidance" set to off and since U.S. 1 crossed I-95 plenty of times up ahead I stayed on I-95. The accident was cleared well before we got there and we did not have to detour. Checking later I found that the "Traffic Avoidance" had been changed to "ON" and I set it back to "OFF". Guess what? A couple of map changes later it happened again! So, since then I check all my settings after a map update.

Map accuracy is getting better and more companies are ensuring that the data submitted is accurate (well, at least most are). Although the other day I was adding a new BoA ATM in RI and Google Maps was wrong. I copied and pasted the address and hit enter. Google Maps displayed the location as a convenience store/garage. Going to street view I looked around and saw no ATM. So, back out to map view, no balloon for BoA. I then checked the few surrounding balloons for addresses. The correct address was 1/2 block away on the other side of the street! Street view showed an empty storefront there, so I'm assuming that was it (I put "Approx" in the "C" column as I usually do with no visual).

So to cure the incorrect POI locations here, I advise all POI file maintainers here to verify that the L/L is as close as possible by using "Street View" in Google Maps, especially if you are adopting an existing file.

To correct map errors, you need to contact the map creator - NOT Garmin. Garmin uses maps supplied by "HERE". Their website is here.com .

Routing errors should be sent to Garmin. They will need to know the model and map version, as well as a detailed explanation of the problem. Incorrect business or other locations that cause routing errors should be sent to "Here", NOT Garmin.

I plan to create a FAQ to help file maintainers to better organize and maintain the files they own in Excel (or OpenOffice). There are some tricks I use to to get the data from Google Maps to a file and also to easily get the data to Google Maps and verify L/L. I know a lot of maintainers use Extra Poi Editor to check their work, but with Google constantly changing their code we do not know how long it will work and TURBOCC is currently unable to update his program. So, if there is a code change that makes Extra POI Editor not work at all, you'll have to revert to the old methods.

I've rambled enough and probably bored a lot of members - Later.

The map makers depend on the businesses to supply the location data to them and assume it is correct. There are a probably a lot of errors due to Fatfingers and not knowing how to get the correct L/L. Google Maps and "HERE" maps have pages that allow businesses to enter the location. They do not take it upon themselves to do this. Entering "every" business location in the USA into a map would probably increase the size of a map to over 20 Gigs or more and put so many balloons on the GPS that you would not be able to see the streets in some locations. You would have to turn that feature off, which would also turn off the "Custom" POIs on most GPS devices.

Every now and then, it is good to take stock of how maps are created and how businesses are located on those maps. It is NOT an exact science. Think about all of the road construction that you see around you. We should not expect the maps we use to incorporate these changes until the construction is completed and someone has time to "map" the changes into the next map release - which may be months in the future.

I have often encountered a slightly different problem with "mailing addresses" versus "location" in POI files. In new developments (say shopping centers), early tenants may be given an address that does not reflect their actual location in the development. A POI developer gets the address and turns it into L/L but that may be way off from the L/L that someone would want to navigate to.

The files that I maintain are not so large that I cannot actually inspect each location using Extra POI Editor (EPE). Further, doing so lets me set the L/L to the most appropriate entrance off of the road. So - anyone wanting alerts "along the road" will get them. If I used the L/L of the "front door" and that was more that 30 meters from the "center of the road being traveled on", an alert would not sound.

Thanks to metricman for his thoughts.

Garmin stated at one point early on that it obtained its list of businesses and their addresses from Dunn & Bradstreet business files. It was shown that the D&B addresses were often mailing addresses and not necessarily the brick and mortar location as it was originally gleaned from business licenses or incorporation paperwork. These were often obtained long before the business had a physical location. It bis entirely possible some of those addresses still linger in Garmin's list.