Question: Thiepval Barracks is located in a city that is part of what metropolitan area?
Sentence (from "Tri-Cities metropolitan area"): As of April 1, 2017, the Washington State Office of Financial Management, Forecasting Division estimates the population of the metropolitan area to be 283,830, making it the fourth-largest metropolitan area in Washington, after Seattle-Tacoma, Spokane, and Vancouver (Part of the Portland metropolitan area).
Relevant evidence: No