Billed as a "vertical pier" by architects Marks Barfield, it's symbolic that the silver spire with its glass donut of a pod, 12 years in the making, is open 150 years after Eugenius Birch's West Pier first gave visitors to Brighton a unique view of the seafront.
The pier's charred remains are all that's left of the Grade 1 listed structure, which was closed in 1975 and burned down in 2003. The i360 rises almost from its ashes — the pier's dilapidated 19th century Italianate toll booths have been carefully reconstructed and stand proudly at either side of the steel tower, one as a ticket office and one a tearoom, bringing old and new together in vivid contrast.
The giant glass bubble can carry 200 passengers and has a shiny Nyetimber Sky Bar that serves sparkling wine from the Sussex vineyards visible from the pod, as well as other locally produced drinks. Besides soaking up the views, it's mesmerising to watch the honeycomb-patterned steel cans that form the world's most slender tower slip through the centre of the pod.
Most importantly for my two-year-old son, Ollie, the pod is buggy friendly, meaning babies and toddlers can enjoy the whole ride from the comfort of their pushchairs.
The STG46 million ($A80 million) project, expected to generate 440 new jobs in Brighton and Hove, is part of a wider regeneration effort by the city council in what's being dubbed the "Creative Quarter". The Victorian West Pier Arches on either side of the tower, under the seafront road, were rebuilt from scratch and opened in July 2014 as cosmopolitan-feeling galleries, craft and boutique gift shops.
As we discover during a long weekend, Brighton is a child's paradise, with endless hours of fun to be had for kids of all ages — even the grown-up variety.
Across the road from the West Pier Arches, we stay at the 131-room Holiday Inn, which has also just undergone a major refurbishment, giving its muted lobby a stylish Scandi feel, and ultra-comfy seaview rooms.
As part of the makeover, there's a Starbucks in the hotel bar — perfect for a late-night coffee — and trendy American diner-style restaurant Stock Burger Co., complete with milkshakes in old milk bottles with red and white-striped straws, and delicious chicken burgers.
The beauty of Brighton — and the hotel's underground car park — is you can leave your car safely stowed and forget about it for an entire weekend, because all the fun stuff is well within walking distance.
Opposite the hotel is an extremely handy playground with clean sandpits, and a coffee shop and souvenirs in the arches, where mum and dad can grab a cappuccino to sip while little ones build sandcastles to rival the i360, which towers above.
The beach is a sweeping pebbly affair, not sandy, with a steep bank of stones that's great for sliding down towards the sea. With a son obsessed with shells, we're slightly surprised to discover just one variety — the common slipper limpet — on our beachcombing expeditions, but they're in plentiful supply and we soon have a bagful to cart home and display proudly alongside the garden snail collection.
A sea-smoothed stone's throw away is The New Club, which opened its doors in 2013 after gutting a near-derelict premises, an early sign of gentrification in this part of the city by the sea. All high ceilings, large windows and a massive mural of a New York apartment block, it oozes Manhattan warehouse chic and serves great food.
The BBQ Halloumi is a riot of colour and texture, with giant couscous, quinoa, coriander and pomegranate all fighting for attention on your palate.
It's also highly child friendly, with baby changing and a menu for little ones — plus crayons delivered to the table as soon as we sit down.
From here, it's a leisurely 15-minute stroll up to the eastern seafront, and the unexpected highlight of our visit: the aquarium. Resplendent in its original 1872 Victorian stone arches, it's the world's oldest operating aquarium — and somewhere you can easily lose three hours. Incredibly for a Saturday, it has a relaxed atmosphere and there's not too much of a queue in the ocean tunnel, where black tipped sharks and sea turtles swim over your head.
New for 2016 and unmissable is the Seahorse Nursery, where the curling tails of these strangely beautiful creatures will mesmerise you.
In the new Secrets of the Reef section, there's what we come to call the "Nemo tunnel" — a cleverly built tank of clown fish that allows little ones to walk right through the middle. We take no time finding Dory, too ...
Walking round slowly can be oddly tiring, so we stop at the central cafe to refuel before exploring the nearby Ray Pool and Rock Pool, where Ollie touches a starfish and a crab for the first time.
We wend our way into the famous Lanes, a warren of narrow streets filled with antique shops, the fascinating Armoury and the honeypot window displays of avant garde chocolatier Choccywoccydoodah. A busker plays classical guitar, as the day gives way to evening and the pace of bustling street life slows.
Dinner is at the vegetarian jewel in the crown of Brighton's gourmet scene: Terre a Terre.
Some waxy Wikki Stix are magicked up for Ollie, which he bends into worms and wheels, while we pore over the menu.
Classically trained chefs Amanda Powley and Philip Taylor opened the restaurant in 1993 to push the boundaries of meat-free cooking, and the tastes they've concocted are mind blowing.
The tapas sharing platter includes their Bangkok Balls — coconut rice balls loaded with toasted peanuts, pistachio puree and Thai basil, and that's just for starters.
We leave to find the sun setting over the sea. There's just enough light to pose for photos behind "Afloat", Hamish Black's vertical bronze donut of a sculpture, and for a ride on the carousel. From high on my fairground horse, I watch couples walk along the beach hand in hand, as the sun dips down behind the shell of the old pier.
And, just to its right, the more modern horizontal donut, the British Airways i360, rises above the city, a beacon of hope for Brighton's bright future.
- PA