# Help me think in Kilometers. **URL:** \ **Category:** In My Humble Opinion\ **Created:** [April 9, 2009, 2:59pm UTC](https://boards.straightdope.com/t/help-me-think-in-kilometers/492512 "2009-04-09T14:59:48Z")\ **Posts on this page:** 3\ **Page:** 3
**Author:** ![Electronic\_Chaos](https://avatars.discourse-cdn.com/v4/letter/e/bbe5ce/32.png) [@Electronic\_Chaos](https://boards.straightdope.com/u/Electronic_Chaos)\ **Post date:** [April 12, 2009, 4:40pm UTC](https://boards.straightdope.com/t/help-me-think-in-kilometers/492512/41 "2009-04-12T16:40:55Z")
Here’s the obligatory [xkcd](http://xkcd.com/526/) link, discussing practical (and hilarious) metric reference points. Everyone should have this printed out and laminated! ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [April 13, 2009, 2:37am UTC](https://boards.straightdope.com/t/help-me-think-in-kilometers/492512/42 "2009-04-13T02:37:23Z")
> [@Muffin](#): > > Yes, you are correct. In Ontario, concession roads were determined by lot size, which in turn was calculated in acres (10 square chains or one square furlong equal one acre). 10 square chains = one acre, but 10 square chains != one square furlong. One furlong is ten chains, so an acre is a furlong-chain. (Plough one furrow long, time to turn the team round. Plough a chain’s width of furrows, time to knock off for the day.) It’s a rectangular definition, not a square one. A square furlong is ten acres. It just happens that a chain is pretty close to 20 metres, so the 1000-acre lot is close to a 2km square. ---
**Author:** ![Muffin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/muffin/32/4341_2.png) [@Muffin](https://boards.straightdope.com/u/Muffin)\ **Post date:** [April 13, 2009, 2:42am UTC](https://boards.straightdope.com/t/help-me-think-in-kilometers/492512/43 "2009-04-13T02:42:51Z")
Thanks! [Previous page](https://boards.straightdope.com/t/help-me-think-in-kilometers/492512.md?page=2)