Uniformly mesoporous and thermally robust anatase nanorods were produced with quantitative yield by a simple and efficient one-step approach. The mechanism of this process was revealed by insertion of Eu3+ cations from the reaction medium as luminescent probes. The obtained structure displays an unusually high porosity, an active surface area of about 300 m2g−1 and a specific capacity of 167 mA h g−1 at a C/3 rate, making it attractive as an anode electrode for Li-ion batteries. An additional attractive feature is its remarkable thermal stability; heating to 400 °C results in a decrease in the active surface area to a still relatively high value of 110 m2 g−1 with conservation of open mesoporosity. Thermal treatment at 800 °C or higher, however, causes transformation into a non-porous rutile monolith, as commonly observed with nanoscale titania.