Simplify the following text for a Grade 10 native English-speaking person.
Original: Pakistan has a cultural and ethnic background going back to the Indus Valley Civilization , which existed from 2800 â `` 1800 B.C. , and was remarkable for its ordered cities , advanced sanitation , excellent roads , and uniquely structured society .
Simplified: Pakistan has a lot of wealthy cultural and ethnic background going back to Indus Valley Civilization , 2800 BC â `` 1800 BC .