What does it mean exactly when a ride notes a certain amount of elevation? Is this the net of climbing and descents? Sorry, but I'm usually a pure bred flat-lander!

Add up all the climbing you do uphill and disregard the downhills.

So, if you were to start at sea level, go consistently uphill to an elevation +1000 feet, the consistently downhill to an elevation of 500 feet, then consistently uphill back to the elevation of +1000 feet, then finally, a consistent downhill back to sea level, your total climb would be 1500 feet.

Hi,

All circular rides would be zero. As said you add up the ascents and ignore descents.
A real roller of a course, hardly flat, just up and down all the time with no big hills might
appear to be much worse than it actually is, compared to the simple example above.

rgds, sreten.

Thanks!

To add a bit here, in addition to total elevation, you'll also commonly see tougher climbs on a ride broken out with the elevation for them segregated from the total amount in many cases. A lot of more serious riders like to test their performance on particular climbs and are interested in tracking both the elevation gains and the gradient increase percentages for those. This is especially true for those who perform well on the flats, but are a bit "allergic" to hills

When I look at a new route or upcoming race I always figure the climbing at feet per mile. For instance a 40 mile ride with 1,500' of ascent would equal 37.5 feet of climbing per mile which would not be significant. However a ride that is 40 miles with 4,500' of ascent would equal 112.5 feet of climbing per mile and that would be a very hard effort for me.