Highest point reached for 170 new homes at Neptunus in Maarssen

Last Saturday, the construction team of Neptunus reached the highest point of the building, marking a major milestone for this new development at Het Kwadrant in Maarssen. Of course, this was celebrated on site by everyone involved in bringing the project to life. With the structure now complete, attention shifts to the next phase: giving it its final shape! 

From structure to finishing

Reaching the highest point of a building is one of the most visible milestones in any construction project. It marks the moment a development stops being a steel and concrete frame and starts taking its final shape. For everyone involved, from the construction crew to the project developers, it's a moment worth celebrating on site.


The final element is being transferred into place on the roof of Neptunus, marking the highest point of the building. Photo: SBB Ontwikkelen en Bouwen. 

The construction team lining up for a well-earned treat from the frietkar, a small celebration of reaching the highest point of Neptunus. Photo: SBB Ontwikkelen en Bouwen.

Now that the highest point of Neptunus has been reached, the construction team is shifting its full attention to the rest of Neptunus. The facades will be finished with brickwork, and the windows will be installed floor by floor. Once the building is closed, the focus moves indoors, where installations, finishing, and interior works can continue. 

The low-rise section already shows how the finished development will look. It's now fully bricked, the roofing is in place, and finishing works are well underway inside. It offers a clear preview of what the rest of the building will look like once construction is completed.

More about Neptunus

Once finished, Neptunus will offer 170 rental studios and apartments, ranging from compact city homes to more spacious layouts. Every home will have large windows for plenty of daylight, and Neptunus will carry an A+++ energy label, supporting energy-efficient living for future residents.  

Neptunus is part of the new Ruimtekwartier in Maarssen, right next to our other building in Maarssen: Boomerang. So, residents of Neptunus will find a familiar Holland2Stay community already established right around the corner! This project consists of two buildings, of which Neptunus will house homes for rent. As more of the Ruimtekwartier area develops around it, this area is set to become a lively, green addition to Maarssen.

Neptunus' location in Maarssen puts residents within easy reach of Utrecht and Amsterdam. Living in Maarssen offers a quieter residential setting while keeping both cities within convenient commuting distance. For those who enjoy spending time outdoors, the nearby Maarsseveense Plassen is perfect for swimming, walking, or simply unwinding after work or study.

• 170 rental studios and apartments, ranging from compact city homes to more spacious layouts
• Located at Het Kwadrant, right next to our Boomerang building
• Built around a shared green courtyard
• Energy-efficient living with an A+++ energy label
• Part of the new Ruimtekwartier neighborhood in Maarssen

One of the defining features of Neptunus is the shared courtyard, creating a place to sit outside, get some fresh air, or simply enjoy a quieter view than the street outside. 

What's next? 

Completion of Neptunus is planned for Q4 of 2026. With the structure now complete, the building is steadily moving toward a finished home for future residents. The next months will bring visible progress on the outside, as brickwork and windows close up the facade floor by floor, while teams continue working on the interior finishing.  

We'll continue sharing updates as construction progresses toward completion. Want to be among the first to hear when Neptunus' residences are ready to book? Sign up for updates.