The Hotelling-Clawson procedure for estimating the demand for recreation resources assumes only one destination with no close substitutes. Knesset in 1963 states, "One factor which is of particular importance in describing the demand for any single recreation area is the availability of close substitutes." The problem of estimating the demand for wilderness use in California is an example where the availability of close substitutes will influence both the estimation technique and the determinants accounting for wilderness use. Alternative estimation techniques are presented and tested in this paper to account for differences among destinations. The results indicate that then dealing with a multi-area wilderness system assumptions with regard to the structure of the system must be explicitly stated and tested.