I am a 51 year old convicted felon. Drug & assault charges from prior to 1985. Along with several drunk driving tickets. Have not had any charges or arrest since 1986. I am planning a trip to Canada next summer and want to make sure I will be allowed in the country.

Apply for rehabilitation. Depending on your circumstances it may be granted based on the nature of your visit.

Thought it might be helpful to include a website about how to do this

Overcoming criminal inadmissibility

There is a 65-35 chance that you will be denied entry into Canada.The Canadians take the drunk driving charges very seriously and more so after the American immigration authorities started to crack down on canadians with offenses like consuming marijuana which is not consider that big of a crime in Canada and hence its "tit for tat" at the border posts.

You may want to be very careful, my uncle had a DUI on his record from about ten years ago and he tried to go to Canada fishing this year, and they wouldn't let him across the border. Ty but that's their law.