The city's first separated bike lanes officially opened along Sherbourne Street today as part of a cycling network being planned for the downtown core.

Marked in green, the lanes are billed as a way to offer cyclists a measure of protection against cars. In some sections, the lanes are protected by a curb, though in others only a strip of paint separates bikes from vehicles.

"It's definitely faster for cyclists and it allows drivers and cyclists to know exactly where they're supposed to be — there's no guesswork," cyclist Chris Drew said.

The lanes cost $2.5 million and will mean the loss of some street parking along Sherbourne, with the designated zone stretching from King Street to Bloor Street.

Coun. Denzil Minnan-Wong appeared on CBC Radio’s Metro Morning on Monday and said while the lanes won’t satisfy all cycling advocates, they are an important first step in improving bike access to the downtown core.

"For sure, if you hit the raised curb you're gonna know about it, and your car is gonna know about it, and it's not going to be something you're going to want to do," he said.

Minnan-Wong said the Sherbourne bike lane will be followed by similar lanes on Wellesley Street by the end of the year. There are also plans for lanes on Adelaide and Richmond streets, which are undergoing an environmental assessment.

Some cyclists have complained drivers continue to block the bike lanes, a $150 fine.

"There's still a lot of people illegally parking on the bike lanes," Drew said.

Minnan-Wong said it was a "significant problem" that can be fixed by "more parking enforcement."

Other cyclists are also not happy that a bike lane on Jarvis Street was installed then removed by the city in a controversial decision that cost hundreds of thousands of dollars.

At the ribbon cutting ceremony this morning to officially open the Sherbourne lane, Mayor Rob Ford said it was only the first phase in the 14-kilometre cycling network being planned for Toronto.

"I think this is the first step in having an integrated bike lane system down here, and that's what the people want downtown," Ford said.