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Surgical treatment of tendon lesions still yields unsatisfactory clinical outcome. The use of bioresorbable scaffolds represents a way forward to improve tissue repair. Scaffolds for tendon reconstruction should have a structure mimicking that of the natural tendon, while providing adequate mechanical strength and stiffness. In this paper, electrospun nanofibers of two crosslinked PLLA/Collagen blends (PLLA/Coll-75/25, PLLA/Coll-50/50) are developed and then wrapped in bundles, where the nanofibers are predominantly aligned along the bundles. Bundle morphology is assessed via SEM and high-resolution x-ray computed tomography (XCT). The 0.4-micron resolution in XCT shows a biomimetic morphology of the bundles for all compositions, with a predominant nanofiber alignment and some scatter (50%-60% were within 12° from the axis of the bundle), similar to the tendon microstructure. Human fibroblasts show good viability and growth over 7, 14 and 21 days. The stiffness, strength and toughness of the bundles are comparable to tendon fascicles, both in the as-spun condition and after crosslinking, with moderate loss of mechanical properties after ageing in PBS (7 and 14 days). PLLA/Coll-75/25 has more desirable mechanical properties such as stiffness and ductility, compared to the PLLA/Coll-50/50. This study confirms the potential to bioengineer tendon fascicles with enhanced 3D structure and biomechanical properties.