Tokyo has magnetism, and it feels endless. What hits you first is the scale. There’s the neon signs, the ancient temples, the skyscraper skylines, all of it mixed together. In the metro area there are more than 35 million people; that’s like taking two-thirds of England and putting it into one city – and then expecting the trains to run on time and the traffic to flow.

I grew up in Madrid and London and now live in LA, but Tokyo is my spiritual homeland. I grew up with Japanese cartoons, comics and video games and was strongly drawn to the country from as far back as I can remember; they were my earliest experiences of storytelling, so it’s perhaps no surprise I ended up writing my novel, Blue Light Yokohama, in Tokyo.

Tokyoites are fond of reminding people there are more Michelin-stars there than in London and Paris. Meals don’t have to be expensive to be good, though. On a recent trip, my girlfriend and I visited Jigokudani snow monkey park and, while waiting for the bus to Tokyo, ended up eating in what was essentially a man’s house. He made us ramen and watched TV with his kids while we ate. You can’t Google or Street View things like that.

When I first visited in 2010 I was told by a salaryman in a bathhouse that “Tokyo is a million cities”. It seems that way. Harajuku on a Saturday is, essentially, a teenage catwalk with people in the latest fashions swarming all around; but it’s only a 10-minute walk to the Meiji Jingu shrine, where there may be a traditional wedding with a bride in an incredible white kimono and headpiece and priests wearing clogs.

Todoroki Ravine park is one of the Tokyo’s most beautiful sights but is easy to miss. It’s a surprisingly leafy city full of secrets. The park is actually a green secluded lane that flanks a river and has stone carvings, old bridges and bamboo groves. While walking you can smell moss and hear the bells of a temple.

I’d choose a trip to Mount Takao over Mount Fuji. It’s a beautiful and not-too-taxing route up and there’s a beer garden at the top. Also, if you go to one of the sushi bars just before they close, they’ll usually load up the plate, as fishery laws mean there’s a time limit on how long it can be served for.

Rainbow bridge is illuminated by solar power and spectacular when it’s lit up – it’s my favourite view in Tokyo. Those who don’t mind heights can cross it on foot and see glittering vistas of the city, while the water below is lit by the reflected neon of passing party boats.

Visitors shouldn’t worry that Tokyo will be overwhelming, or you won’t understand anything if you don’t speak Japanese. Many signs are in English and people will fall over themselves to help you. Pick up either a Suica or a Pasmo card: they’re similar to London’s Oyster travelcard, but in Japan they can be used to buy things in shops, too. The official Go Tokyo website is handy for the essentials and has apps for exploring the city, including a subway journey planer. The website Tokyo Free Guide arranges free walking tours, too.

If you don’t fancy starting the day at 3am, give Tsukiji fish market a miss and visit the Metropolitan Government Building Observatory instead. It’s free, and so tall your ears will pop in the lift to the top. There are views out to Mount Fuji, it has a cool gift shop and is just as beautiful by day as at night.

Yakitori is the place for street food, especially Memory Lane. Much of it consists of grilled meat on skewers that’s salted and glazed. Memory Lane (or Piss Alley, depending on who you ask) has red lanterns and exposed wires, all crammed beneath train arches; it’s Blade Runner and old Japan all at once.

There’s a photo of me and a friend sitting by the river in Yokohama with a beer looking out at the neon, it’s my favourite shot from my first trip. It was the first “extreme destination” assignment I’d been sent on as a writer for Which? travel magazine. I was in my mid-20s and so excited. The tour group I was with were all older, so I bonded with the guide, a French guy who had married a Japanese woman. Neon illuminates the water and Yokohama’s ferris wheel is in the background. We’re deep in conversation, but both of us are looking out to the water.

My obsession with capturing the spirit of Tokyo on page means my relationship with it is very special – even though the city is oblivious! I spent two years researching Blue Light Yokohama, which shares its title with a love song, by Ayumi Ishida that was number one in Japan over Christmas 1968. Yokohama used to have gas streetlamps and they glowed blue. The lyrics are a bit eerie because, instead of singing about her lover, Ishida is singing to the city instead.

• Blue Light Yokohama by Nicolás Obregón is out now (Michael Joseph, £12.99). To order a copy for £11.04, including UK p&p, visit bookshop.theguardian.com or call 0330 333 6846