| VERST | Russian length equal to 3,500 ft. |
| SAGENES | Russian length units |
| LINEARB | 3,500-year-old writing deciphered in 1953 |
| CRETE | Vacation locale with 3,500-year-old ruins |
| GAP | Chain with more than 3,500 stores worldwide |
| SPAN | 3,500 feet, for the George Washington Bridge |
| HGV | Lorry weighing over 3,500 kg for short (3) |
| ANSTRUTHER | Town in Fife (pop about 3,500), the site of the Scottish Fisheries Museum (10) |
| AVIEMORE | Town In the Highlands (pop about 3,500), a popular resort (8) |
| YARD | Imperial unit of length equal to 3 ft, 36 in or 0.9144 m (4) |
| FATHOM | Unit of length equal to six feet, used to measure depths of water |
| ANGSTROM | Unit of length equal to one hundred-millionth of a centimetre, used mainly to measure electromagnetic wavelengths and atomic distances (8) |
| HAND | Old unit of length equal to four inches used for measuring the height of horses, typically from the ground to the withers (4) |
| METRE | Unit of length equal to 100cm, 299,792,458 of which equate to the distance of one light-second (5) |
| MILE | Unit of length equal to 5,280 feet |
| STATUTEMILE | Unit of length equal to 1,760 yards |
| KMS | Units of length equal to 1,000 meters, briefly |
| INCH | A unit of length equal to 2.54cm (4) |
| HM | A metric unit of length equal to 100 meters. |
| KILOMETRE | Unit of length equal to 0.621 mile (9) |
