Lorraine Shemesh Swimming Pool Paintings

Water as a barrier
http://www.lorraineshemesh.com/

Trees as barriers

Trees as barriers, views through.

Craig Stephens Bridges and Dams

http://craigstephens.blogspot.com/

Craig Stephens is a practicing Artist and Art teacher in California. Amazingly as well as holding down a full time job he is producing a painting a day and exhibiting them on his Blog

A Dam as a barrier holding back the water

A bridge as a barrier