GO train passengers on the Barrie Line through western Toronto had their commuting experience quite literally elevated today with the start of service on Metrolinx's new Davenport Diamond Guideway.

The new 1.4-kilometre-long elevated rail line was initially scheduled to begin service on March 27, but was delayed at the very last minute when Metrolinx concluded it required more time for testing, and later revised the opening date to April 4.

Continued progress on the Davenport Diamond Guideway: Running test trains before the start of revenue service trains. Stay connected for more updates. pic.twitter.com/qvbMeAkLnm

— GO Expansion (@GOExpansion) April 3, 2023

That date arrived this morning to much fanfare from railfans, and despite a bit of rain obscuring passengers' views on the first commuter trains using the new infrastructure, the response has been overwhelmingly positive.

The Davenport Diamond Guideway has officially opened! Conditions weren’t ideal for filming, but here’s the eastward view from the new guideway. Timestamps:
0:00 - Davenport Rd
0:25 - CP North Toronto sub
0:32 - Dupont St
0:56 - Wallace Ave
1:15 - Bloor St W pic.twitter.com/47nYqurQVy

— Zach 🚏🚌 (@VanishingUnder) April 4, 2023

Completion of the Davenport Diamond Guideway overcomes a significant hurdle in Metrolinx's plan to introduce all-day, two-way GO service on the Barrie Line.

Flying over Bloorcourt pic.twitter.com/O9CSCyHx8e

— Sean Marshall (@Sean_YYZ) April 4, 2023

Prior to the guideway's installation, trains on the Barrie Line had to yield the right-of-way to freight on the intersecting CP rail line in what was — until today — one of the busiest rail intersections on the continent.

F59s at speed! pic.twitter.com/UfrKXrbshe

— Urban Cayman (@ProjectEND) April 3, 2023

The guideway's bypassing of this at-grade intersection brings Metrolinx a step closer to its promise of enhanced service on the Barrie Line by eliminating a bottleneck in traffic.

Starting today, trains are using the elevated guideway as part of the Davenport Diamond Grade Separation project.

This brings GO Transit one step closer to providing high-frequency RER style regional rail to an entire region and is a huge milestone pic.twitter.com/Q5g5hj3hLR

— Jamie (she/they) (@TransitThinker) April 4, 2023

Only a few trips have used the new guideway since the first train passed over it early Tuesday morning, but riders are already reacting to the new addition to their commute. One rider remarked that the trip was "very smooth and quiet."

Just rode the first revenue service train on the Davenport Diamond Grade Separation project

The ride was very smooth and quiet! pic.twitter.com/xn3oxmOG5e

— Jamie (she/they) (@TransitThinker) April 4, 2023

The opening comes as a quiet success amid Metrolinx's continued struggles with the delay-plagued Eglinton Crosstown LRT. The much more complex megaproject has been under construction for well over a decade, and an opening date has still not been provided to the public.