The early morning rush hour is not a good time to be out and about in Bangkok.
Bangkok's main roads are often packed with traffic
The roads are jammed and irritated faces glare out from behind the wheels of cars, buses and taxis, all struck in the heavy traffic.
But on Monday the traffic seemed a little lighter, and the commuters on foot even seemed to have a spring in their step.
For many in this vast sprawling metropolis, the morning commute has just become much easier - thanks to Bangkok's new subway system.
Opened on Saturday by Thailand's revered King Bhumipol Adulyadej, more than 200,000 curious passengers travelled on the 32 km of underground network over the weekend.
But the real test came on Monday, when the crowds of morning commuters tried out the new system.
"It's great," said Wallaya. "It used to take me more than an hour to get to work. Today the journey only took 30 minutes, and I had to queue at the ticket office for quite a long time. It's going to mean I can spend longer in bed!"
Security guard Wattana was equally impressed.
"Normally I travel on the bus, and it takes at least half an hour, even though I don't live very far from here. Today it took about 10 minutes."
It is not just a question of speed. Many Bangkokians are impressed by the slick stations, the German-engineered trains and the banks of escalators carrying passengers into the bowels of the city.
Commuters say the new subway is fast and efficient
"It's much easier than the Skytrain," said businessman Steve, referring to the city's other major public transport network.
"I can take my son to school and we don't have to climb up all the stairs. The escalators make things much more convenient," he said.
The metro runs in a semi-circle from the north to the south of the city.
Although the 18 stations on its route are still out of reach for many people who live in Bangkok's suburbs, the network penetrates much further than the above-ground Skytrain, which only runs through the city's business district.
There are also plans to extend the metro network to reach more commuters.
The authorities plan to build another 60km of tunnels within the next six years, which the government hopes will cut Bangkok's legendary traffic congestion by 50%.
The Chairman of the MRTA ( Mass Rapid Transport Authority), Prapat Chongsanguan, is optimistic about the future of the network.
Not everyone will benefit from the new subway
"We've had a few problems, and we need to educate the public about how to use the ticket tokens, but overall we've had a very favourable response from people," he said.
"I think the big test will come in a month's time, when the proper ticket prices are introduced.
"When the price goes up to 30 baht (75 cents) per journey, we will get a true reflection of how many passengers are really using the system."
But not everyone was thrilled with the new subway network.
Just outside Saladaeng interchange station, a rank of motorcycle taxis stood idle. The drivers, who would normally be winding through the traffic, were chatting about Sunday's Euro 2004 football final.
And another Bangkok institution might be under threat.
"I haven't had a fare all morning", complained Somchai, as he sat in his colourful Tuk-Tuk.
"If this goes on, I'll have to look for another job.
"Or maybe I should just move to another city."