My current project to create a complete dataset of airborne LiDAR data for Ohio and Pennsylvania has been teaching me some simple, albeit really powerful tricks. We’ll just discuss one today — recursive use of wget. This allows us to download entire trees of web sites to mirror, or in our case download all the data. Additionally, wget works on ftp trees as well, with no real change in syntax.

wget -r ftp://pamap.pasda.psu.edu/pamap_lidar/cycle1/LAS/

I recognize that curl can be a more powerful utility than wget, but for dead simple problems like this, a dead simple tool is more than adequate.