Edo Castle

Listen for a moment. Behind you, Tokyo hums with traffic and trains. Ahead, there is gravel under your shoes, the slow drip of water against stone, and the call of crows in old pine trees. Huge granite blocks rise from a dark moat, fitted together without mortar. This quiet ground in the middle of one of the largest cities on Earth is what remains of Edo Castle. For more than two and a half centuries, it was the centre of power in Japan.

The story begins long before the shoguns. In 1457, a warrior and poet named Ota Dokan built a fortress here, on a low rise above a fishing village and a marshy bay. The village was called Edo, which means something like "estuary" or "river gate." Dokan's castle was modest by later standards. It was earthworks, wooden walls, and a good view of the water. Few people then could have guessed that this muddy shoreline would one day become Tokyo.

The turning point came in 1590. Tokugawa Ieyasu, one of the most careful strategists in Japanese history, received this region and made the small castle his base. He did not stay modest for long. After he became shogun in 1603, Edo became the seat of the Tokugawa shogunate, the military government that ruled Japan until the 1860s. Ieyasu and his successors turned the old fort into the largest castle complex in the country.

The scale of that work is hard to picture. Hills were cut down. Marshland was filled in. Rivers were moved, and a spiral of moats was dug outward from the centre. The shogunate ordered the regional lords, the daimyo, to supply labour, money, and stone. Much of the granite came by boat from the Izu Peninsula, south of here. Each lord competed to show loyalty, and the cost helped keep them too busy and too poor to rebel.

Here is a detail many visitors walk past. Look closely at the large stones in the walls. On some of them, you can find carved marks — circles, lines, small symbols. Many of these are thought to be the signs of the work crews or the lords who supplied the stone. They were a way to track whose contribution was whose. Four centuries later, those marks still sit in the walls, worn but readable.

If you entered through the Otemon, the main gate, you followed the same route that visiting lords once took. The gates here were designed as traps. Many have a square courtyard between two entrances, so an attacking force would be caught in a closed space and shot at from above. Further in, you pass the Hyakunin-bansho, the Hundred-Man Guardhouse. Its long wooden hall once held shifts of armed guards who watched every person heading toward the inner castle.

Now walk up to the open lawn of the Honmaru, the innermost circle of the castle. Today it is a wide, calm field of grass with trees at the edges. Once, this space was packed with buildings: offices, reception halls, and the private quarters of the shogun and his household. The women's quarters, called the Ooku, held hundreds of women and was closed to almost all men. Very little of all this survives above the ground.

At the north end of the lawn stands a massive stone platform. This is the base of the main keep, the tall central tower. The keep burned in the Great Fire of Meireki in 1657, a disaster that destroyed much of the city and killed many thousands of people. The stone base was rebuilt afterwards, but the tower itself was never replaced. The government decided the money was better spent rebuilding Edo. You can climb to the top of the platform and look out over the gardens.

One more story lives on these grounds. Somewhere near the edge of the Honmaru, a small marker shows the site of the Pine Corridor, a long hallway decorated with paintings of pine trees. In 1701, a lord named Asano Naganori drew his sword here and attacked an official named Kira Yoshinaka. Drawing a blade inside the castle was a grave crime, and Asano was ordered to take his own life. His loyal retainers later took revenge. Their tale became the story of the Forty-Seven Ronin, still retold in Japanese theatre and film.

Take a look, too, at the Fujimi-yagura, a white three-storey watchtower on the southern side. Its name means "Mount Fuji viewing tower." It is one of the few original defensive buildings still standing. After the keep was lost, this tower took on some of its role as a symbol of the castle. On clear winter days, people once said, you could see the mountain from its upper windows. Today, modern buildings make that view much harder.

The end of the shogunate came in 1868. As imperial forces approached the city, the two sides negotiated, and the castle was handed over without a battle. That peaceful surrender saved Edo from destruction. The young Emperor Meiji moved here from Kyoto, and the city was renamed Tokyo, which means "eastern capital." The old castle of the warriors became the home of the imperial family.

That is why this place feels divided today. The western part of the old castle grounds holds the Imperial Palace, where the Emperor still lives and works. Most of that area is closed to the public, except on special days or on guided tours. The eastern part, where you are now, became the East Gardens, opened to the public in 1968. Here, you can walk freely among the walls, gates, and gardens of the shoguns.

Before you leave, spend some time in the Ninomaru garden, on the lower level. It is a classic Japanese strolling garden, with a pond, a small waterfall, stepping stones, and carp moving under the surface. Each season changes it. There are plum blossoms in late winter, cherry blossoms in spring, irises in early summer, and red maples in autumn. Office workers come here at lunch to sit on the benches and eat in silence.

As you walk back toward the gate, look again at the stone walls. They were built to show power and to stop armies. Now they hold up moss and small ferns, and joggers run past them every morning on the path around the moat. The city outside has changed beyond recognition. But the stones are the same ones that the daimyo's crews lifted into place, block by block. Put your hand on one, if you like... and listen for the water.