OTA with nostalgic database

Is there a such thing as a database or OTA like Expedia for flights of the past? I mean, you put in a year and two cities and you can see flights available, etc. What has me thinking about this is that I took a couple of trips in the 70s from SFO to MEX via LAX on Western (on the DC-10!), but we lived near SJC, and I have always wondered why we went all the way to SFO to start the trip.

I used Flightstats.com in the past for historic flights, but right now their service is not free.

How far back does it go?

“The underlying data currently includes flights back to February 7th, 2006.”
Well, it is not so far back in the past.
I do not know if you email the airport to ask them if they have some records or something.