Tel Aviv kicked off its 100th birthday celebrations in April, beginning with the international Centennial Conference on Urban Sustainability on the history and future of development in the city. One panel focused on the ongoing threat of eviction that several hundred Jaffa families currently face in light of encroaching gentrification. Prof. Rachelle Alterman of the Technion-Israel Institute of Technology told the audience that while awareness was changing and more attention being paid to the needs and rights of Jaffa's Arab residents, the city was still not making the community's social and economic development a top priority. Real-estate developer Alon Kastiel said that gentrification would continue, and solutions for Jaffa's development needed to be reached through greater cooperation between City Hall, government institutions and local community leaders. During a panel on architecture, Lodovico Folin Calabi of the UNESCO World Heritage Center was asked to address the issue of development versus preservation. Calabi questioned the wisdom of allowing skyscrapers in and around historical areas. Conservation, he said, should be seen not as an obstacle to development, but as a tool for it. Calabi was followed by architect Amnon Bar-Or, who described the planning process that led to the construction of the Neveh Tzedek tower, a 44-story residential building in the low-rise Neveh Tzedek neighborhood near Jaffa. Bar-Or criticized the structure as a barrier between Tel Aviv and Jaffa, instead of a connecting link. The day's discussions culminated in a panel entitled "The Vision of Tel Aviv 2025." Mayor Ron Huldai listed the city's accomplishments in recent years and called for a metropolitan transport authority to fulfill Tel Aviv's urgent need for efficient public transportation. He also expressed his wish that Tel Aviv would "preserve its democratic, tolerant and pluralistic spirit" over the next century. City Engineer Hezi Berkowitz presented a blueprint for city growth over the next decade and a half. The plan envisions several new large-scale projects, including a new airport on an artificial island off the coast; a seaside park and new urban quarter in the northwest; a subway system and new roads and bike paths; new parks; cultural and entertainment districts; and several large office developments - including Complex 2000, a new skyscraper district located on what is now the Arlosoroff train station. The event garnered criticism for high ticket prices, which kept many residents away, and for allegedly excluding the various green organizations that are active in promoting sustainable urban planning in Tel Aviv, including the Israel Bicycle Association, the Society for the Protection of Nature in Israel (SPNI) and its "Green Forum." City Hall rejected this criticism, telling Metro: "The environmental organizations were not only invited, but their representatives took an important part in the conference, and were included as partners in the process of planning the conference, as well as on the various panels." However, there were also signs that City Hall is taking more of an interest in sustainability than it has in recent years. Several veteran activists expressed satisfaction that city officials were at least beginning to use the language of sustainability in their presentations. As one municipal official put it: "These days we are definitely green, we're just not quite sure what that means yet." Popular local blogger Yoav Lerman wasn't convinced, dismissing the panel discussions as "bad and boring," noting that Tel Aviv is actually moving away from the principles of urban sustainability by becoming more car-dependent and less pedestrian-friendly.