Why are 35 and 40 acre lots Common in Colorado?

If you’ve grown accustomed to social distancing and are searching for your cabin site in the woods, you may have noticed that country properties in Colorado are frequently offered in increments of 35 or 40 acres.  There are reasons behind this.  Explaining 40 acre lots goes back to the original government surveys, most of which happened in the 1800’s.  Surveyors broke down sections of land into 6-mile square townships.  Each township has 36 numbered sections.  Each section is one square mile consisting of 640 acres.  Those sections are further broken down into quarters.  Each of those quarters are broken down again into quarters.  A quarter section is 160 acres and a quarter-quarter is 40 acres.  When you see a 40, 80, 160, etc. acre parcel, the legal description will often be described using this Public Land Survey System (PLSS).  35 acre lots are common because of a 1972 law in Colorado that restricted a landowner’s ability to simply split off anything less than 35 acres.  Commonly known as Senate Bill 35, it required landowners to go through a subdivision approval process for parcels smaller than 35 acres.  Parceling land into lots greater than 35 acres does not require approval (although some counties in Colorado have a higher acreage requirement), which is why we often see parcels offered in 35-acre increments.