: Economical power use is essential to allow for long-lasting operation of wireless sensor networks. This applies equally to linear sensor networks as they emerge when sensors are deployed along bridges or pipelines. In this work, we present MERR (Minimum Energy Relay Routing), a novel approach to energy-efficient routing to a single control center in a linear sensor topology. Based on an optimal transmission distance, MERR finds paths that minimize total power consumption. Our analytic and simulation results show that MERR saves significant power compared to conventional approaches and has near-optimal performance.