Capt> Thanks for the insight, I guess I understood what you were suggesting and I think I will try the boulder/fence/dense forest to keep my “treasures” from tumbling.
In my last layout, i did raise the fascia about 1 1/2" above the 4x8’ but I thought it looked hokey and I never (knock on my wooden head), had a derail that fell off the table or rails for that matter.
But probably just a matter of time, especially with son-in-laws and grandkids who think it is the most fun to run as fast as possible and maybe even crash the locos. [sigh]