# Ships pass port-to-port, why? (History) **URL:** \ **Category:** Factual Questions\ **Created:** [October 30, 2015, 7:16am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161 "2015-10-30T07:16:42Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![SpyOne](https://avatars.discourse-cdn.com/v4/letter/s/82dd89/32.png) [@SpyOne](https://boards.straightdope.com/u/SpyOne)\ **Post date:** [October 30, 2015, 7:16am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/1 "2015-10-30T07:16:42Z")
I get that having uniform regulations helps everybody. But until fairly recently (past 300 years or so), the standard for land travel was keep left. It would make sense for sea travel to follow the same standard, _unless there was some good reason not to_/. Since the standard is to pass an oncoming ship with both of you keeping right, I assume there was a good reason to pick that instead of the opposite. But my google-fu has utterly failed in producing that reason. And so I crowd-source my question to a group of people with very broad interests. Why was port-to-port chosen as the standard for how ships should pass? ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [October 30, 2015, 8:18am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/2 "2015-10-30T08:18:38Z")
> [@SpyOne](#): > > Since the standard is to pass an oncoming ship with both of you keeping right, I assume there was a good reason to pick that instead of the opposite. Why make that assumption? One side had to be picked, it could have been entirely arbitrary couldn’t it? ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [October 30, 2015, 8:24am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/3 "2015-10-30T08:24:24Z")
[Tillers mounted on the side](https://en.wikipedia.org/wiki/Steering_oar) used to be the standard way of steering, and [would be mounted on the starboard](https://en.wikipedia.org/wiki/Port_and_starboard#/media/File:Tapisserie_bato1.jpg) (“steer board”) side (because lefties are of the Devil or something), if you pass on the left (port) you run the (minimal, IMO, but _yo no soy marinero_.) risk of those binding. So passing on the right may have become standard for that. ---
**Author:** ![lisiate](https://avatars.discourse-cdn.com/v4/letter/l/f05b48/32.png) [@lisiate](https://boards.straightdope.com/u/lisiate)\ **Post date:** [October 30, 2015, 8:24am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/4 "2015-10-30T08:24:51Z")
Maybe because steering oars were on the starboard side? So port-to port collisions won’t take out the steering as well. ETA: bah ninjaed ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [October 30, 2015, 1:26pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/5 "2015-10-30T13:26:13Z")
That just restates the question, though. Why were steering oars on that side? Is it easier for a right-handed person to manipulate one that way? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [October 30, 2015, 1:28pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/6 "2015-10-30T13:28:56Z")
> [@](#): > > But until fairly recently (past 300 years or so), the standard for land travel was keep left. Until much more recently than that, there was no standard for land travel at all. When America chose keep-right and Britain chose keep-left, neither one was breaking with tradition, because there wasn’t any to break with. ---
**Author:** ![dofe](https://avatars.discourse-cdn.com/v4/letter/d/7ba0ec/32.png) [@dofe](https://boards.straightdope.com/u/dofe)\ **Post date:** [October 30, 2015, 1:51pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/7 "2015-10-30T13:51:01Z")
> [@ElvisL1ves](#): > > That just restates the question, though. Why were steering oars on that side? Is it easier for a right-handed person to manipulate one that way? Because having the tiller on the port side of the boat makes it hard dock the boat to the port. Although this answer may simply raise a chicken or egg question… ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [October 30, 2015, 2:38pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/8 "2015-10-30T14:38:05Z")
> [@ElvisL1ves](#): > > That just restates the question, though. Why were steering oars on that side? Is it easier for a right-handed person to manipulate one that way? I’d think that you’d want to stand facing forward, holding the tiller/steering oar next to you with one hand. And right-handers would want to hold it with their right hand most of the time. So they’d want the tiller/steering oar on the right side of the boat. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [October 30, 2015, 3:10pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/9 "2015-10-30T15:10:13Z")
If ships are passing port-to-port, then they are traveling in opposite directions. In most of the world, cars do the same. If aircraft are traveling in the same direction, the overtaking aircraft passes to starboard, which I presume is part of the nautical tradition. ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [October 30, 2015, 3:14pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/10 "2015-10-30T15:14:00Z")
Aircraft heading toward each other also divert to the right. It may be because pilots generally sit on the left side of the airplane, and can more easily see the aircraft being overtaken that way. So why do pilots generally sit on the left side? 😉 ---
**Author:** ![Duckster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/duckster/32/1244_2.png) [@Duckster](https://boards.straightdope.com/u/Duckster)\ **Post date:** [October 30, 2015, 3:19pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/11 "2015-10-30T15:19:12Z")
> [@ElvisL1ves](#): > > So why do pilots generally sit on the left side? 😉 Because the copilot sits on the right side, silly. 😃 ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [October 30, 2015, 3:37pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/12 "2015-10-30T15:37:04Z")
> [@ElvisL1ves](#): > > That just restates the question, though. Why were steering oars on that side? Is it easier for a right-handed person to manipulate one that way? Did you look at the Bayeux pic I linked to? Also consider the[standard gondola layout](https://en.wikipedia.org/wiki/Gondola#/media/File:Venice_Gondola_Grand_Canal.jpg) (though that’s a combo rowing/steering ore). Yes, it’s easier for righties. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [October 30, 2015, 4:01pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/13 "2015-10-30T16:01:59Z")
> [@Quercus](#): > > I’d think that you’d want to stand facing forward, holding the tiller/steering oar next to you with one hand. And right-handers would want to hold it with their right hand most of the time. So they’d want the tiller/steering oar on the right side of the boat. Besides, the left side is [EEEEVUL](https://en.wikipedia.org/wiki/Bias_against_left-handed_people). And [sailors are superstitious](https://en.wikipedia.org/wiki/Sailors%27_superstitions). Certainly, you wouldn’t steer your ship from the EVIL side, would you? Clearly, that would be as unlucky as a woman named “Jonah” whistling while eating bananas on board. 😃 ---
**Author:** ![leahcim](https://avatars.discourse-cdn.com/v4/letter/l/b4bc9f/32.png) [@leahcim](https://boards.straightdope.com/u/leahcim)\ **Post date:** [October 30, 2015, 4:45pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/14 "2015-10-30T16:45:25Z")
Like which side you drive on, there is little material difference between “everyone passes on the right” versus “everyone passes on the left”. The is great benefit to choosing one of those vs. “everyone picks the side they want”. ---
**Author:** ![Bijou\_Drains](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bijou_drains/32/2814_2.png) [@Bijou\_Drains](https://boards.straightdope.com/u/Bijou_Drains)\ **Post date:** [October 30, 2015, 8:09pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/15 "2015-10-30T20:09:14Z")
I thought riding your horse on the left was done because most people are right handed. Which meant they could hold a weapon (like a sword) in their right hand to fend off an attacker if needed. ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [October 30, 2015, 9:18pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/16 "2015-10-30T21:18:18Z")
If you don’t pass [port to port](http://4.bp.blogspot.com/--ForXuI7Dlo/U9aYo_-M_MI/AAAAAAAAB7k/EJkz7TangFo/s1600/StockholmDoria.jpg), [bad things](https://malcolmoliver.files.wordpress.com/2015/09/andrea-doria-life-magazine.jpg) happen. ---
**Author:** ![Snnipe\_70E](https://avatars.discourse-cdn.com/v4/letter/s/b5a626/32.png) [@Snnipe\_70E](https://boards.straightdope.com/u/Snnipe_70E)\ **Post date:** [October 31, 2015, 2:07am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/17 "2015-10-31T02:07:21Z")
> [@Jackmannii](#): > > If you don’t pass [port to port](http://4.bp.blogspot.com/--ForXuI7Dlo/U9aYo_-M_MI/AAAAAAAAB7k/EJkz7TangFo/s1600/StockholmDoria.jpg), [bad things](https://malcolmoliver.files.wordpress.com/2015/09/andrea-doria-life-magazine.jpg) happen. By the Rules of The Road a Starboard to Starboard passing is permitted if the ships are at a wide enough angle. But the ship not in the right away position must signal their intent. And it is also their responsibility to be sure the ship in the right away understands their intent. The Andrea Doria had a sloppy helmsman, and The Stockholm missed the intent of the Andrea Doria. And Bad thing did happen. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 31, 2015, 3:37am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/18 "2015-10-31T03:37:01Z")
> [@Bijou\_Drains](#): > > I thought riding your horse on the left was done because most people are right handed. Which meant they could hold a weapon (like a sword) in their right hand to fend off an attacker if needed. That is the story for horsemen. Wagon team drivers originally sat on the left rear horse in the team to keep their right hand free to hold a whip, so they’d keep the wagons to the right side so they could clearly see the left side of the wagon and the left wheels as they passed another wagon coming from the opposite direction to prevent collisions. The countries that drive on the wrong side of the road used the horse model for cars instead of the more appropriate wagon model. ---
**Author:** ![Morgenstern](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@Morgenstern](https://boards.straightdope.com/u/Morgenstern)\ **Post date:** [October 31, 2015, 6:17am UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/19 "2015-10-31T06:17:00Z")
I think it had something to do, long long ago, with weapons being carried in the right hand. That’s why the English drive on the left side of the road (traditionally)- they can draw their sword and defend themselves. Something like that. ---
**Author:** ![SpyOne](https://avatars.discourse-cdn.com/v4/letter/s/82dd89/32.png) [@SpyOne](https://boards.straightdope.com/u/SpyOne)\ **Post date:** [October 31, 2015, 5:03pm UTC](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161/20 "2015-10-31T17:03:28Z")
> [@Chronos](#): > > Until much more recently than that, there was no standard for land travel at all. When America chose keep-right and Britain chose keep-left, neither one was breaking with tradition, because there wasn’t any to break with. While it was not made a _law_ before then, > [@](#): > > This practice of (traveling) on the left, was formalised in a Papal Edict by Pope Benedict around 1300AD who told all his pilgrims to keep to the left. (Taken from [Why do the British (and the Japanese) drive on the left? | aperi mentis](https://aperimentis.wordpress.com/2013/01/20/drive-on-the-left/) ) (Similar quotes found on many other sites.) [Next page](https://boards.straightdope.com/t/ships-pass-port-to-port-why-history/736161.md?page=2)