1 century = 100 years

The 25th Century BC includes all the years from 2500 BC to 2401 BC.

Right now, as we write this, the year is 2011. The 25th Century BC was

the period from 4,511 years ago to 4,412 years ago.

487 BC

The year 340 BC is classified as the 4th century BC.

895 BC is in the 9th century BC.

It is in the middle of the 8th century BC.

The years 1 to 100 BC (inclusive) are the 1st century BC.

101 to 200 are the 2nd century BC

201 to 300 are the 3rd century BC

301 to 400 are the 4th century BC

401 to 500 are the 5th century BC

501 to 600 are the 6th century BC

601 to 700 are the 7th century BC

701 to 800 are the 8th century BC

. . . and so on.