I have a 1999 cannondale road bike which I've used for many years as a SS in NY, but now i live out in the woods and the 23mm tires do not seem up the job of the rough dirt roads around my house. The main problem is I tried putting 35mm Schwallbe marathon plus tyres(NUCLEAR BOMB PROOF) on the bike but they do not fit.

Anyone out there got any experience with any tires that they use on road as well as off road (gravel roads mostly). I'm hoping that I might be able to use 28mm.

If all else fails i been looking around at maybe a cheap touring/cycle crosss frame that can take up to 38mm tires.
I was interested in the NYCbike frames but was put off a little by the negative vibes on the forum towards them. Then i seen a touring frame at Nashbar(cringe) for around $200 which was light and would hold the right tyres for the job.

It's very tough to juggle a wife with no interest's in cycling and the desire to buy new a new bike.

thanks