Fellenzer Engineering LLP Share: Engineering/Land Surveying Fellenzer Engineering LLP Visit Website Request Info 22 Mulberry Street, Suite 2A Middletown, NY 10940 (845) 343-1481 (845) 343-4986 (fax) Facebook About Map About Fellenzer Engineering LLP, a nationally recognized engineering firm, leads the Hudson Valley in innovative engineering consultation, analysis and design.Our award-winning designs have earned us What's Nearby? Distance: 5 10 15 20 25 50 mi.