I'll give you a time travel / post-apocalypse twofer:

The Nantucket Series (Island in the Sea of Time, Against the Tide of Years, and On the Oceans of Eternity) by S.M. Stirling are about an event that transports the island of Nantucket back to the Bronze Age where the residents must adapt to their new surroundings and learn how to survive without modern technology.

The Emberverse Series (Dies the Fire, plus several others) is the flip-side to Nantucket. The same event that created the bubble that sent Nantucket back in time also irrevocably altered the laws of physics in the modern world.such that electricity, guns, explosives, etc. no longer work. Society collapses and devolves into a more medieval system.

Both are excellent series and can be read independently of each other, but there are some elements that weave between the two. The Emberverse series is still ongoing, with a tenth book due out this coming September.

Yep, Ron's right. Those series of books are pretty good.

I have them all, but only have read about 4 of them. S. M. Stirling is a good writer, but he does get ponderous at times. It slows the pace and storyline to a grinding halt. The details are wayyyyy overwritten at times.

That's one of the reasons I've had them so long, but haven't finished them. Once of several books or book series that are in my personal slush pile.

Oh, I almost forgot!

The Timewars series by Simon Hawke was excellent! Some were better than others, but the first 6 or so books were great, if memory serves me right. They came out somewhere between the late 80's and early 90's. 

Posted By Ron Miles on 3/15/2013 8:24:01 PM

I'll give you a time travel / post-apocalypse twofer:

The Nantucket Series (Island in the Sea of Time, Against the Tide of Years, and On the Oceans of Eternity) by S.M. Stirling are about an event that transports the island of Nantucket back to the Bronze Age where the residents must adapt to their new surroundings and learn how to survive without modern technology.

The Emberverse Series (Dies the Fire, plus several others) is the flip-side to Nantucket. The same event that created the bubble that sent Nantucket back in time also irrevocably altered the laws of physics in the modern world.such that electricity, guns, explosives, etc. no longer work. Society collapses and devolves into a more medieval system.

Both are excellent series and can be read independently of each other, but there are some elements that weave between the two. The Emberverse series is still ongoing, with a tenth book due out this coming September.

Started reading dies the fire an age ago but for some reason or other started reading Island in the sea of time instead. I love his books although some times he does go into too much detail but the man can really write an action scene. William Walker is a great villain, I always want my baddies to be real bastards.