The fort at Phillaur, about 35 kilometres southeast of Jalandhar on the Grand Trunk Road, was built by Maharaja Ranjit Singh in 1809 to guard the crossing of the Sutlej. It is a substantial squat structure with corner bastions and a moat, and it sits on what was the frontier between Sikh and British territory. After 1846 the British took it over and added the buildings that still house the Maharaja Ranjit Singh Punjab Police Academy.
The fort is on the active police training campus and access is restricted; you generally need to write ahead or persuade the gate. With permission, the original Sikh-era walls and underground passages are visible and the views over the Sutlej from the bastions are worth the visit. The Grand Trunk Road itself, threading through Phillaur town, is one of the great pieces of subcontinental infrastructure — Sher Shah Suri's 16th-century highway, still in use.