The River Fleet, the grail of London. The first stop for any drainer passing through our sleepy shores. Its astonishing mix of large tunnels, gigantic chambers, intriguing features and historical value is enough to make even the strongest of men weak at the knees.

The Fleet, previously a major tributary of the Thames, once served as a shipping dock at its mouth. This is where it got the name fleot, meaning "tidal inlet". Eventually changing to Fleet as time went by. Unlike many of the other "Lost Rivers", the Fleet has attained a cult interest and a certain degree of infamy. Basically meaning, if you talk about it, eight times out of ten people will understand and not look at you like your speaking Klingon.

My partner for tonight's activities was JonDoe, mystic holy man and seasoned sewer frequenter from Sub-urban. After a quick hello and brief bits of small talk we stood above the cover. The warm soapy smell of the Fleet rushed past me as we opened the manhole. I grabbed my bag and down we went, entering the tomb of a once mighty serpent. Brick passageways span of in every direction, old signs showing the way to new travelers.

Due to the Fleets relationship with the Thames, it is incredibly tidal. The main outfall chamber manages to fill to the roof in under 30 minutes. I.e., if your in the wrong end of the room, your screwed. At some point the water level has risen up a further two flights of stairs and into the main access tunnels. Scary!. Even as we approached low tide the water was still over four meters deep, so we had to hang around on the upper levels to let it empty.

We walked the old passages, old shoes and tools lay propped up against the walls. We ended in a small room housing a crank for one of the Low Level Sewer Sluice gates. Ill be honest, it looked like it was made of chocolate, but the kind you didn't want to put in your mouth.

While JD was taking a quick snap, i headed off to get a quick look at the mainline sewer. Just as i was about to christen my waders with the freshness of the Fleet, a thunderous bang shook the tunnels. I'm pretty sure i added to the flow content at that point, what the hell was that?. Again, Bang. I started to get a little worried this time, Bang, Bang!. BANG. This time getting peppered with chunks of golden nuggets falling from the roof. Not good, for more then one reason. I headed back to find JD, smirking slightly at my panicked state. Turns out, it was a boat passing by on the Thames. As it passed, the boat had sent surge waves back up the tunnel, causing the flood gates to open and then bang shut.

We continued through the passages and came into a three tiered chamber. If you imagine a large Battenburg cake, then add another half on top of that, you'll get the idea. The top tier housing two emergency flood gates, which if needed could be lowered into a fixed position in the middle level. The middle and lower levels also contained their own flood gates, which connected to the outfall chamber on the other side.

Splash, touch down. Never before have i been so happy to see sewage on my feet. The main sewer was a gigantic 15ft high oval pipe, containing the remains of the Fleet, now diluted with the flow from several sewers. A small barrier has been constructed to divert all regular flow into the low level, but the weird part was underneath. In the non existent gap between the final beam and the floor, a small rat had comedically been jammed in, its legs just sticking out.

By now the water in the outfall chamber has receded, revealing a 2ft pit of Thames riverbank sludge. This honestly smelt worse then the sewer itself. A small frog suffered the wraith of a photographically challenged JD, pushing it from the ledge while trying to get it to look at the camera. Down the steps and into the sludge i went. My waders instantly covered in a dark brown/black liquid mess. The outfall from Wren's Cache flowing in from the left.

While taking photos JD shouted across to me "CRAB". Screw that, i turned around expecting to see something from a japanese b-movie coming towards me. He waved me over, and sure enough on the wall was a tiny baby crab, only about an inch or two wide, its shell almost see through. By this time my torch was almost dead, so we called it a day and started to head back to the entrance. Up the ladder and out, being passed by a load of scantily clad drunk girls.

To date we have now explored almost all of the "known" Fleet sewer, finding yet more baffling and beautiful features and with it more tales to tell. But for now you'll have to make do with the one you just read. Hey, if you want an idea times the above by 10, and you still wont come close. The River Fleet is, and forever will be, legendary.