Why are all the state capitals in the US in relatively small cities?

The capital of NY is in Albany, not NYC. The capital of PA is in Harrisburg, not Philadelphia The capital of TX is in Austin, not Dallas Houston Is there a reason (national security for example) to establish the state capitals in relatively non-significant cities, or this is purely due to some tradition in the past?

Public Comments

1. Each state wrote its' own history. National security wasn't a concern. Some capitals were chosen for central locations. In the old days, it was much more difficult for legislators to travel than today.
2. Austin IS a big city, several hundred thousand. Salt Lake City is big, Denver is big, Sacramento is big, Phoenix is big, Honolulu is big, Oklahoma City is big, Atlanta is big, etc, etc. You said ALL state capitals are big.
3. In some cases, central location. Harrisburg, PA, Jefferson City, MO, Springfield, IL, Columbia, SC.
4. They are designed so that they do not attract attention to their decisions.