I found something neat on Craigslist, 24" gauge tracks and a small locomotive from a mine but the seller doesn't know much about them as they belonged to his dad previously. At $75 a track I really like the idea of having a 120ft oval loop around my backyard.

Can anyone help me compute just how much track I need to pull this off, especially with the curves? I really have no experience with anything bigger than some model trains on this.

https://sfbay.craigslist.org/eby/for/d/san-ramon-24-gauge-railroad-train-track/7658009797.html