While online mapping tools are plentiful, they may not all accurately reflect the true dimensions of your property. The best way to get an accurate representation of your property lines is through a professional site survey.
However, Oregon City does provide some mapping tools you may find useful in helping you map your property: OC Web Maps.
Oregon City's in-house GIS mapping tool, OCWebMaps, contains maps of the approximate locations of your property lines. It's helpful to show the ways in which certain overlays - like Natural Resources, Geologic Hazards, and Floodplains - interact with your property. However, while helpful in planning any projects you might have, OCWebMaps is not an accurate substitute for a professional survey by a licensed surveyor.
Plat Finders
Oregon City's in-house Plat Finders can help establish certain dimensions that may prove helpful in determining property lines. However, they are not substitutes for a professional survey.
Clackamas County Tax Maps
Clackamas County's Tax Maps (CMaps) are created to display the dimensions of properties for which taxes are assessed and may not accurately depict your property lines.