The Tennis Court (aka the Dennis Court) was built by Clark and first appeared in Episode 90 - Deadly Tennis,where Zack and Clark proceeded to have a deadly Tennis match. This consisted of shooting arrows at each other until one of them died. The survivor was pronounced winner.
The Tennis Court currently sits in a state of disrepair and is unused as of the Episode 300 save. It is believed to have been purposely demolished, as Clark's area is now the site of SwimmingBird941's area.