The Dartford Tunnel is actually two tunnels—one for northbound traffic, one for southbound—under the River Thames. Each one is 1.4 miles long (or about 2.3 kilometres for the metric-minded). That’s it. You could walk it in about 25 minutes, if you fancied a lungful of diesel fumes and existential dread. But let’s be real: you’ll spend at least that long queuing to get into it.
Fun fact: the first tunnel opened in 1963. It was so narrow and dark that driving through it felt like being swallowed by a concrete snake. The second tunnel arrived in 1980, doubling the misery—er, capacity. Today, the whole Dartford Crossing (tunnels plus the famously ugly QEII Bridge) handles over 150,000 vehicles a day. That’s more cars than there are people in a small city like Oxford. Imagine every single Oxford resident driving a car through your living room, and you’re close.
