The station has a new concourse and atrium the size of a football pitch
The new-look Birmingham New Street station was praised by many of the thousands of rail passengers passing through during its first rush hour.
The £750m refurbishment has seen a new concourse, huge atrium and Grand Central shopping complex built.
Some passengers said it was stunning and imaginative, with beautiful lines.
However, one told BBC News that platforms and trains would still be overcrowded as "aesthetics don't improve function".
Andrea Robinson also told BBC Midlands Today that she felt the station was "hideous", with "style over substance as usual with modern design".
New Street's clear roof is made of a similar material to that used at the Eden Project in Cornwall
The barriers opened for their first rush-hour on Monday
The last major redevelopment of the station was in the 1960s
It is the first major construction project on the station since it was redeveloped in the 1960s.
Previously known for being one of the city's concrete landmarks, the station's new mirrored shell is in stark contrast to its past, with its clear roof allowing natural light to pour in.
More escalators and lifts have been added to platforms.
When it opened in 1854, New Street featured the largest iron and glass roof in the world, but the damage it sustained during World War Two led to its 1967 concrete reincarnation.
More than 6,000 tonnes of concrete have now been removed to allow light to fall on to the concourse.
Commuter Nathan Webb told BBC News: "About time New Street got a facelift. City centre needs it."
Anna Baker added: "Stunning. Can't wait for the whole complex to be up and running. Now all we need are a few practical tweaks - a drinks fountain so travellers can fill their water bottles, and somewhere to park your bottom when the train is delayed."
The Grand Central shopping centre, with a flagship John Lewis store, is due to open on Thursday
On social media, there have been many positive and negative reactions as about 170,000 commuters are due to pass through on Monday ready to catch one of the trains that leave every 37 seconds.
When New Street opened in 1854, it featured the largest single-span iron and glass roof in the world. Platform two, pictured here, was made from both stone and timber
One commuter tweeted that it's all glitz and no service. It is still "tiny crowded dirty dark platforms", he said.
Jerzy Klein, who was commuting from Digbeth to Birmingham Business Park in Solihull, said there were no bins for smokers outside the entrance which led to "butts building up for months", although they have mostly been cleaned away in time for the reopening.
Pointing to crowds piling through just one of more than 10 double doors at that entrance, he said the station was still hard to navigate.
"I commute every single day and the way the station is designed, the flow of people is wrong," he said.
More than 6,000 tonnes of concrete have now been removed to allow light to fall on the concourse for the first time since the 1960s' redevelopment
Commuter and electrician Andrew Mincher said the station was "nice until you looked up"
"Everyone is moving the same way and it is difficult to get to your platform among a river of people. Shopping centre aside, [the revamp] has not improved anything for the commute."
Andrew Mincher, an electrician at Birmingham University who commutes from Great Barr, said he was impressed but that it was "nice until you look up", referring to some overhead wiring visible in part of the station.
The redevelopment is part of a wider revamp of the city centre with a flagship John Lewis store and the Grand Central shopping complex opening on Thursday.
Andy Street, managing director of John Lewis, said it was a great time to come to the city and the new store would draw in shoppers from across the Midlands and beyond.
Immy Kaur, of Impact Hub Birmingham, said the city was really proving itself as a place for business to thrive, with its low living costs and "beautiful soul".