The grid system (1)

At last, I've worked it out. The enormous numbers which are used to identify houses in the US (and Canada come to that), frequently running into the thousands, have always mystified me. I could never work out why they were necessary. For example, we live at number 2809, but there are nowhere near 2809 houses in our road - in fact there are barely 28. So why such numeric amplification?

I finally realised why the other day. We had a parcel delivered, addressed to the previous occupants of our house. I tried phoning UPS to explain, but after several minutes wrestling with the automated voice recognition system ('Say 'pick up' to arrange a pick up, say 'track' to track a parcel, or say 'lose the will to live' if your enquiry doesn't fit neatly into one of these five very limited options we have decided in our wisdom to offer you') I gave up and decided to deliver it myself. Their new address was not far away, quite close to the 'downtown' (city centre) area.

The road I needed was 15th Street NW. I already knew this meant it would be north-west of the city centre, 15 streets up from the nominal 0th Street, in fact called (slightly confusingly) Reno Avenue here (in the American grid-system, Streets usually go west-east while Avenues go north-south - anyone who's visited Manhattan will know this). So I drove down Pennsylvania Avenue until I hit 15th Street, and turned right (west) onto it. The numbers were far too high and going higher (I needed 1005), so I turned round and started going back (east, towards downtown). I noticed that the numbers on the houses were round about the 2800 mark. What a co-incidence, I thought - similar to my own house. And then I realised that it wasn't a co-incidence. I was directly south from where I lived, albeit several miles south. And the numbers here were the same.

As I drove east, I realised that the first two digits of the house numbers were getting progressively smaller - 27, 26, 25, 24 - more quickly than the quantity of houses would seem to warrant. They do the same thing on our road, going east. The reason why they were getting smaller so quickly was that there were only ever a few houses - say 4 or 5 - for each of these initial numbers. Typically, they might go 2612, 2608, 2604, 2600 ... then you'd get 2512, 2508... etc. I realised that each of these intial numbers (26, 25 etc.) covered a distinct distance. It obviously wasn't a full 'block', as these are a mile square - they were obviously sections of blocks, or mini-blocks.

I also noticed that all the even numbers were on the south side of the street, and all the odd numbers on the north side - just like our street. The only thing I couldn't work out, and still can't, is why the numbers go in fours, not in twos like the British system. In other words, what happened to 2602, 2606 and 2610? They don't seem to exist. But again, it's consistent - our neighbours are 2805 and 2813, while over the road are 2808, 2812 and 2816.

After I crossed the next major avenue, I noticed that the numbers had gone down to 19, 18... And then it hit me - the distance covered by each is precisely one-tenth of a block, because the initial digit corresponds to the block itself. Numbers beginning with a 2 are obviously 2 blocks away from the city centre - although to be precise, they will be at least two whole blocks away and therefore in the third complete block, because houses in the first block have a nominal zero in the front, so you get numbers like 908, 912 etc. - it's like when you are 37 years old (as I am now), you are actually in your 38th year of life. And presumably really near the centre, there are even coveted two- and even one-digit addresses - wow, imagine the cachet they must bring! - although thinking about it, I suppose they should also exist further away from the city centre, branching off either side of 0th Avenue.

It struck me that the beauty of this system is that if you know that the address of the building you want is, say, 1712 NW 49th Street, you should be able to pinpoint pretty much exactly where it is, on an actual or mental map of the city - 49th street north of the centre, one and three-quarter blocks west, south side of the street. And this will be the case even if - as is the case with our road - the street in question doesn't extend across the full extent of the city, but starts and stops somewhere in the middle. The numbering will start and finish according to its geographical position relative to the city as a whole. In the UK, if you're told that an address is 28 Watson Road, you have absolutely no idea - unless you consult a map or just happen to know - where Watson Road is, or which direction it goes in, or how far along the road the building is (the numbering could start from either end). Having said that, you don't, of course, know where Reno Avenue is unless you happen to know it's also 0th Street, so the system only works in full for numbered streets and avenues, as opposed to named ones. I suppose even Americans find a complete absence of street names a bit clinical.

And by the same token, you often get the same street or avenue name being used in completely different parts of the city, because of course sometimes roads don't extend all the way from one side to another without a break (there are things in the way, such as shopping malls, freeways, railroads, schools, factories, etc.) For example, there are bits of Shartel Avenue running right the way from the extreme north to the extreme south of Oklahoma City, even though they are effectively completely separate from each other, and in some cases a very long way apart. That's quite confusing to a British person, but again, very logical when you think about it.

I remember reading somewhere that the American grid system of city planning was first established in Philadelphia (was it Jefferson who invented it, or someone like that?) and proved so popular that it was swiftly adopted by all subsequent cities. I already knew that the grid system was logical and made it very easy to get about, but I hadn't appreciated before the full extent of the practical ramifications.

One thing still bothers me. Where we live, eleven blocks north of the centre, you get addresses on the avenues like 10100. Logical, certainly - but how do you say this number? I fervently hope it's 'one hundred and one hundred' (like 'twenty seven hundred') and not the persuasively shorter but clearly logically incorrect 'ten one hundred'.

And what about the house I was looking for, 1005 15th Street? It didn't exist! There was a park in the way. I found out later I had the wrong address. But it wasn't a wasted trip!