A retaining wall for supporting and stabilizing cut or fill areas of excavation and a method of constructing a retaining wall. The wall is preferably constructed by applying the concrete pneumatically. The method comprises installing a backing board while the vertical wall is pneumatically constructed. The backing board may be selectively removed after application of concrete. The footing and vertical wall can be constructed monolithically utilizing this method. This method of construction yields a high strength wall with very few construction steps and uses materials efficiently. The flexibility in the design and advantages regarding accessibility, along with needing fewer workers for construction, are also a large benefit.