Pedj-aa (large Span). Measurements Converter

We only include several basic units here for you to convert historical units to contemporary ones. A more comprehensive list of metric units is available on the main length conversion page.

We only include several basic units here for you to convert historical units to contemporary ones. A more comprehensive list of U.S. units is available on the main length conversion page.

It might be hard to imagine, but these units dates back to 3100 BC. Egyptian people used them 5000 years ago. These units are distant ancestors of US customary units used today.

The values of Greek units varied according to location and epoch. Relative proportions though were generally the same. Greek measures were in general derived from measurement system of Ancient Egypt.

Roman length units were very well defined. The value of the base unit pes (foot) was discovered by John Greaves in 1639 after he made a lot of measurements in the ruins of Rome. Since then we know that the value of one pes was between 0.967 and 0.986 English feet. An accepted modern value is 296 mm. For most Roman units below we give an English equivalent in parentheses.

In various provinces of Spain diferent variations of units were used. The conversions below use Castilian system. Although most of these units are now obsolete, some can still be used today in the countries of Latin America.

These units were used in Portugal, Brazil and other countries of the Portuguese Empire until the adoption of the metric system in 19th century.

There were many local variations; the following are Quebec and Paris definitions

These units were used before adoption of metric system in 1872.

These units were used before adoption of metric system in 1871.

Common measurement system was introduced in Sweden by law in 1665. Since then the system was slightly altered twice: in 1735 and 1855. Sweden switched to metric system in 1889.