Jason Witten on a NFL-USO tour

Dallas Cowboys tight end Jason Witten will embark on a weeklong visit to visit U.S. troops at military bases in Southwest Asia.

NFL players have participated in the NFL-USO tours for more than 40 years.

But Witten isn't going alone.

San Francisco 49ers tight end Vernon Davis, Cleveland Browns tackle Joe Thomas, and Houston Texans defensive end Mario Williams are also going.

The tours have gone to Afghanistan, Bosnia, Iraq, Korea and Somalia among other cities and countries.

Last year, Jared Allen, Danny Clark, Larry Fitzgerald and Will Witherspoon traveled to Iraq and Kuwait along with coaches Tom Coughlin, Bill Cowher, Jeff Fisher, Jon Gruden and John Harbaugh.