For most of its recorded history, the River Thames was London's widest street. Goods moved faster on water than on any road, and until the eighteenth century a single crossing — London Bridge — spanned the tidal city. Watermen, licensed by Act of Parliament from 1555, ferried passengers between hundreds of stairs and landing places. Their shouts of "Oars" defined the soundscape of the riverbank for three centuries. Today the same stretch carries commuter catamarans and sightseeing boats, and thames cruise tickets sold at Westminster Pier trace a route the watermen would recognise almost exactly. The river is tidal as far inland as Teddington, rising and falling roughly seven metres twice daily. That movement shaped everything built along it. Embankment walls designed by Joseph Bazalgette between 1865 and 1870 narrowed the channel, quickened the current, and buried the sewers that had made the Great Stink of 1858 unbearable. The Victoria Embankment, where Westminster Pier sits, is reclaimed ground — land that was water within living memory of the Victorians. What a London river cruise tour reveals is the city's layered chronology compressed into a few kilometres of waterfront. Upstream: the Palace of Westminster, rebuilt by Charles Barry and Augustus Pugin after the 1834 fire, its Elizabeth Tower clock faces seven metres across. Midstream: the reconstructed Globe, Tate Modern inside Giles Gilbert Scott's Bankside Power Station, the Monument to the Great Fire of 1666. Downstream: Tower Bridge, whose bascules have lifted more than a million times since 1894, and the Tower of London itself, begun by William the Conqueror around 1078. Greenwich closes the sequence with Christopher Wren's Royal Naval College and the Prime Meridian. Architecturally, the river is the only vantage point from which these buildings read as their architects intended. Wren designed Greenwich to be approached from the water. The Houses of Parliament present their longest, most elaborate façade — 265 metres of Perpendicular Gothic — to the Thames, not to the street. Bankside's chimney was positioned to answer St Paul's dome across the channel. The river also remains working infrastructure. The Thames Barrier, operational since 1982, has closed more than two hundred times against surge tides. Oyster beds have returned to the estuary; seals breed within the tidal reach. Among the various thames cruise tickets tours departing from Westminster, the quietest offer a reading of London that no bus route can duplicate — a UNESCO-listed riverscape at Maritime Greenwich, seen from the surface of the water that made it possible.