Philadelphia's Chinatown, one of the oldest on the East Coast, is also one of the city's most densely populated neighborhoods. It's also largely built out, with very little land available for building; most construction activity in the neighborhood consists of renovations of or additions to existing structures.

But the neighborhood's fringes do contain vacant land, much of which is used for parking. One of those lots has disappeared to make way for one of the largest new construction projects the neighborhood has seen in some time.

When these photos were taken about two weeks ago, three floors of what will be a nine-story mixed-use structure had been erected at 810 Arch St.

When finshed, the building will have 94 affordable supportive housing units for homeless men and women and the general Center City community. Project HOME owns and will operate the building, which will also have commercial space on its street floor. The architect's rendering below shows what the finished development will look like.

This project, the fourth in a series of Project HOME developments funded by a gift from Leigh and John Middleton, took a little while to make it from idea to reality. The journey began a little more than two years ago with a trip to the Zoning Board of Adjustment. Even though the lot it sits on is zoned CMX-5, the densest mixed-use category in the city's zoning code, the project still required review by the ZBA because it lies in multiple zoning overlay districts whose restrictions applied to the proposed building. The ZBA gave its blessing to the proposed development on Nov. 6, 2012, and a zoning permit to allow construction was issued on Dec. 27 of that year.

A little more than a year passed before the project advanced further. During that time, it was downsized slightly, from 112 units to the current 94. Project HOME took title to the lot from the Philadelphia Redevelopment Authority in a nominal transaction on June 24, 2014, four days after Licenses and Inspections issued the new construction permit for the building.

Ground was broken for the development last September, and progress has been steady since. The building will also have a fitness center, offices for staff providing supportive services for residents, 38 bicycle parking spaces and seven spaces for staff parking. The building is located close to Jefferson Station on SEPTA Regional Rail, Chinatown station on the Broad-Ridge Spur, and the 8th and Market subway complex, enabling residents to access employment throughout the region as well as nearby services.

Project HOME has partnered with the Philadelphia Chinatown Development Corporation on this development, which is designed to create "innovative supportive housing that is compatible with the neighborhood’s character and will expand the diversity of housing opportunities in a multicultural community."

The project is scheduled for completion in October.